Large inter-individual and intra-individual variability in the effect of perceptual load

PubMed Central

Yeshurun, Yaffa

2017-01-01

This study examined whether the recurrent difficulty to replicate results obtained with paradigms measuring distractor processing as a function of perceptual load is due to individual differences. We first reanalyzed, at the individual level, the data of eight previously reported experiments. These reanalyses revealed substantial inter-individual differences, with particularly low percentage of participants whose performance matched the load theory’s predictions (i.e., larger distractor interference with low than high levels of load). Moreover, frequently the results were opposite to the theory's predictions–larger interference in the high than low load condition; and often a reversed compatibility effect emerged–better performance in the incompatible than neutral condition. Subsequently, seven observers participated in five identical experimental sessions. If the observed inter-individual differences are due to some stable trait or perceptual capacity, similar results should have emerged in all sessions of a given participant. However, all seven participants showed large between-sessions variations with similar patterns to those found between participants. These findings question the theoretical foundation implemented with these paradigms, as none of the theories suggested thus far can account for such inter- and intra-individual differences. Thus, these paradigms should be used with caution until further research will provide better understanding of what they actually measure. PMID:28406997

Individual Differences in Human Reliability Analysis

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

Jeffrey C. Joe; Ronald L. Boring

2014-06-01

While human reliability analysis (HRA) methods include uncertainty in quantification, the nominal model of human error in HRA typically assumes that operator performance does not vary significantly when they are given the same initiating event, indicators, procedures, and training, and that any differences in operator performance are simply aleatory (i.e., random). While this assumption generally holds true when performing routine actions, variability in operator response has been observed in multiple studies, especially in complex situations that go beyond training and procedures. As such, complexity can lead to differences in operator performance (e.g., operator understanding and decision-making). Furthermore, psychological research hasmore » shown that there are a number of known antecedents (i.e., attributable causes) that consistently contribute to observable and systematically measurable (i.e., not random) differences in behavior. This paper reviews examples of individual differences taken from operational experience and the psychological literature. The impact of these differences in human behavior and their implications for HRA are then discussed. We propose that individual differences should not be treated as aleatory, but rather as epistemic. Ultimately, by understanding the sources of individual differences, it is possible to remove some epistemic uncertainty from analyses.« less

The pain of a model in the personality of an onlooker: influence of state-reactivity and personality traits on embodied empathy for pain.

PubMed

Avenanti, Alessio; Minio-Paluello, Ilaria; Bufalari, Ilaria; Aglioti, Salvatore M

2009-01-01

The study of inter-individual differences at behavioural and neural levels represents a new avenue for neuroscience. The response to socio-emotional stimuli varies greatly across individuals. For example, identification with the feelings of a movie character may be total for some people or virtually absent for others. Inter-individual differences may reflect both the on-line effect (state) of the observed stimuli and more stable personal characteristics (trait). Here we show that somatomotor mirror responses when viewing others' pain are modulated by both state- and trait-differences in empathy. We recorded motor-evoked potentials (MEPs) induced by Transcranial Magnetic Stimulation (TMS) in healthy individuals observing needles penetrating a model's hand. We found a reduction of corticospinal excitability that was specific for the muscle that subjects observed being penetrated. This inhibition correlated with sensory qualities of the pain ascribed to the model. Moreover, it was greater in subjects with high trait-cognitive empathy and lower in subjects with high trait-personal distress and in those with high aversion for the observed movies. Results indicate that somatomotor responses to others' pain are influenced by specific onlookers' personality traits and self-oriented emotional reactions. Our findings suggest that multiple distinct mechanisms shape mirror mapping of others' pain.

Effect of Different Phases of Menstrual Cycle on Cardio-respiratory Efficiency in Normal, Overweight and Obese Female Undergraduate Students.

PubMed

Samsudeen, Nazrin; Rajagopalan, Archana

2016-12-01

The influence of obesity on cardio-respiratory efficiency in the various phases of menstrual cycle is not well understood until now. As majority of Indian women have a favourable attitude towards participation in sports it is significant to understand the variation in exercise performance during different phases of menstrual cycle to have an optimum performance. To evaluate the endurance capacity and cardio-respiratory responses in normal, obese and overweight female undergraduate students during different phases of menstrual cycle. Twenty normal weight, 20 obese and 20 over weight, unmarried, undergraduate female volunteers between the age group of 18-22 years, were recruited by convenient sampling. Cardio-respiratory efficiency was assessed by cardiac efficiency test, respiratory endurance test and respiratory blast test. Overall, exercise efficiency varied significantly during the different phases of the menstrual cycle with the highest during luteal phase and lowest during menstrual phase. Similar trend was observed in all the three weight sub-categories, but it was statistically significant in the normal and overweight category only. There was no significant difference in blast test during menstrual phase, follicular phase and luteal phase of menstrual cycle among three groups of individuals. Overall the obese and overweight females had a decreased value for blast test compared to the normal individuals. Significant difference was observed in endurance test among follicular and luteal phase of normal females but there is no change in overweight and obese. Significant difference was observed in Peak Expiratory Flow Rate (PEFR) among luteal phase in normal and overweight individuals but there is no change in obese females. Overall obese individuals have a significant low PEFR compared to normal and overweight individuals. Significant increase in cardiac and respiratory efficiency was observed in the luteal phase of the menstrual cycle in normal weight where as in overweight and obese females, there is an overall decrease in fitness capacity with increase in the Body Mass Index (BMI). Therefore, practice of regular exercise and intake of healthy diet which help in reducing the weight and in turn the BMI will help in enhancing the physical fitness of the individuals.

Relationship between rabbit transferrin electrophoretic patterns and plasma iron concentrations.

PubMed

Zaragoza, P; Arana, A; Amorena, B

1987-01-01

Rabbit transferrin (Tf) was studied electrophoretically using 1141 blood samples from individuals belonging to seven populations (Spanish Common, Spanish Giant, Butterfly, Lyoné de Bourgogne, New Zealand White, Californian and New Zealand White X Californian hybrids). No Tf polymorphism was found by starch gel electrophoresis, but six patterns, differing in the presence and/or intensity of three bands ('a', anodic; 'b', intermediate; and 'c', cathodic) were observed by polyacrylamide gel electrophoresis. No genetic model could explain these patterns, since they reflect differences in plasma Tf iron content. The electrophoretic test allowed a direct observation of the relative in vivo levels of the different Tf molecular species; saturated (band 'a', Fe2Tf); semi-saturated (band 'b', Fe1Tf); and without iron (band 'c' Fe0Tf, apotransferrin). The degree of iron saturation of Tf varied among individuals and throughout the individual's life. Specifically, in pregnant females, Fe2Tf and Fe1Tf are generally observed, except in late pregnancy (from day 25 to parturition), when mainly apotransferrin is observed. Significantly, within 24 h post-partum, high levels of Fe2Tf are reached in the female's serum.

Observational practice of incentive spirometry in stroke patients.

PubMed

Lima, Íllia N D F; Fregonezi, Guilherme A F; Florêncio, Rêncio B; Campos, Tânia F; Ferreira, Gardênia H

Stroke may lead to several health problems, but positive effects can be promoted by learning to perform physical therapy techniques correctly. To compare two different types of observational practice (video instructions and demonstration by a physical therapist) during the use of incentive spirometry (IS). A total of 20 patients with diagnosis of stroke and 20 healthy individuals (56±9.7 years) were allocated into two groups: one with observational practice with video instructions for the use of IS and the other with observational practice with demonstration by a physical therapist. Ten attempts for the correct use of IS were carried out and the number of errors and the magnitude of response were evaluated. The statistic used to compare the results was the three-way ANOVA test. The stroke subjects showed less precision when compared to the healthy individuals (mean difference 1.80±0.38) 95%CI [1.02-2.52], p<0.0001. When the type of practice was analyzed, the stroke subjects showed more errors with the video instructions (mean difference 1.5±0.5, 95%CI [0.43-2.56] (p=0.08)) and therapist demonstration (mean difference 2.40±0.52, 95%CI [1.29-3.50] (p=0.00)) when compared to the healthy individuals. The stroke subjects had a worse performance in learning the use of volume-oriented incentive spirometry when compared to healthy individuals; however, there was no difference between the types of observational practice, suggesting that both may be used to encourage the use of learning IS in patients with stroke. Copyright © 2017 Associação Brasileira de Pesquisa e Pós-Graduação em Fisioterapia. Publicado por Elsevier Editora Ltda. All rights reserved.

Inter-observer reliability of animal-based welfare indicators included in the Animal Welfare Indicators welfare assessment protocol for dairy goats.

PubMed

Vieira, A; Battini, M; Can, E; Mattiello, S; Stilwell, G

2018-01-08

This study was conducted within the context of the Animal Welfare Indicators (AWIN) project and the underlying scientific motivation for the development of the study was the scarcity of data regarding inter-observer reliability (IOR) of welfare indicators, particularly given the importance of reliability as a further step for developing on-farm welfare assessment protocols. The objective of this study is therefore to evaluate IOR of animal-based indicators (at group and individual-level) of the AWIN welfare assessment protocol (prototype) for dairy goats. In the design of the study, two pairs of observers, one in Portugal and another in Italy, visited 10 farms each and applied the AWIN prototype protocol. Farms in both countries were visited between January and March 2014, and all the observers received the same training before the farm visits were initiated. Data collected during farm visits, and analysed in this study, include group-level and individual-level observations. The results of our study allow us to conclude that most of the group-level indicators presented the highest IOR level ('substantial', 0.85 to 0.99) in both field studies, pointing to a usable set of animal-based welfare indicators that were therefore included in the first level of the final AWIN welfare assessment protocol for dairy goats. Inter-observer reliability of individual-level indicators was lower, but the majority of them still reached 'fair to good' (0.41 to 0.75) and 'excellent' (0.76 to 1) levels. In the paper we explore reasons for the differences found in IOR between the group and individual-level indicators, including how the number of individual-level indicators to be assessed on each animal and the restraining method may have affected the results. Furthermore, we discuss the differences found in the IOR of individual-level indicators in both countries: the Portuguese pair of observers reached a higher level of IOR, when compared with the Italian observers. We argue how the reasons behind these differences may stem from the restraining method applied, or the different background and experience of the observers. Finally, the discussion of the results emphasizes the importance of considering that reliability is not an absolute attribute of an indicator, but derives from an interaction between the indicators, the observers and the situation in which the assessment is taking place. This highlights the importance of further considering the indicators' reliability while developing welfare assessment protocols.

Testing inter-observer reliability of the Transition Analysis aging method on the William M. Bass forensic skeletal collection.

PubMed

Fojas, Christina L; Kim, Jieun; Minsky-Rowland, Jocelyn D; Algee-Hewitt, Bridget F B

2018-01-01

Skeletal age estimation is an integral part of the biological profile. Recent work shows how multiple-trait approaches better capture senescence as it occurs at different rates among individuals. Furthermore, a Bayesian statistical framework of analysis provides more useful age estimates. The component-scoring method of Transition Analysis (TA) may resolve many of the functional and statistical limitations of traditional phase-aging methods and is applicable to both paleodemography and forensic casework. The present study contributes to TA-research by validating TA for multiple, differently experienced observers using a collection of modern forensic skeletal cases. Five researchers independently applied TA to a random sample of 58 documented individuals from the William M. Bass Forensic Skeletal Collection, for whom knowledge of chronological age was withheld. Resulting scores were input into the ADBOU software and maximum likelihood estimates (MLEs) and 95% confidence intervals (CIs) were produced using the forensic prior. Krippendorff's alpha was used to evaluate interrater reliability and agreement. Inaccuracy and bias were measured to gauge the magnitude and direction of difference between estimated ages and chronological ages among the five observers. The majority of traits had moderate to excellent agreement among observers (≥0.6). The superior surface morphology had the least congruence (0.4), while the ventral symphyseal margin had the most (0.9) among scores. Inaccuracy was the lowest for individuals younger than 30 and the greatest for individuals over 60. Consistent over-estimation of individuals younger than 30 and under-estimation of individuals over 40 years old occurred. Individuals in their 30s showed a mixed pattern of under- and over-estimation among observers. These results support the use of the TA method by researchers of varying experience levels. Further, they validate its use on forensic cases, given the low error overall. © 2017 Wiley Periodicals, Inc.

Global investigation of composition and interaction networks in gut microbiomes of individuals belonging to diverse geographies and age-groups.

PubMed

Yadav, Deepak; Ghosh, Tarini Shankar; Mande, Sharmila S

2016-01-01

Factors like ethnicity, diet and age of an individual have been hypothesized to play a role in determining the makeup of gut microbiome. In order to investigate the gut microbiome structure as well as the inter-microbial associations present therein, we have performed a comprehensive global comparative profiling of the structure (composition, relative heterogeneity and diversity) and the inter-microbial networks in the gut microbiomes of 399 individuals of eight different nationalities. The study identified certain geography-specific trends with respect to composition, intra-group heterogeneity and diversity of the gut microbiomes. Interestingly, the gut microbial association/mutual-exlusion networks were observed to exhibit several cross-geography trends. It was seen that though the composition of gut microbiomes of the American and European individuals were similar, there were distinct patterns in their microbial interaction networks. Amongst European gut-microbiomes, the co-occurrence network obtained for the Danish population was observed to be most dense. Distinct patterns were also observed within Chinese, Japanese and Indian datasets. While performing an age-wise comparison, it was observed that the microbial interactions increased with the age of individuals. Furthermore, certain bacterial groups were identified to be present only in the older age groups. The trends observed in gut microbial networks could be due to the inherent differences in the diet of individuals belonging to different nationalities. For example, the higher number of microbial associations in the Danish population as compared to the Spanish population, may be attributed to the evenly distributed diet of the later. This is in line with previously reported findings which indicate an increase in functional interdependency of microbes in individuals with higher nutritional status. To summarise, the present study identifies geography and age specific patterns in the composition as well as microbial interactions in gut microbiomes.

Investigating systematic individual differences in sleep-deprived performance on a high-fidelity flight simulator.

PubMed

Van Dongen, Hans P A; Caldwell, John A; Caldwell, J Lynn

2006-05-01

Laboratory research has revealed considerable systematic variability in the degree to which individuals' alertness and performance are affected by sleep deprivation. However, little is known about whether or not different populations exhibit similar levels of individual variability. In the present study, we examined individual variability in performance impairment due to sleep loss in a highly select population of militaryjet pilots. Ten active-duty F-117 pilots were deprived of sleep for 38 h and studied repeatedly in a high-fidelity flight simulator. Data were analyzed with a mixed-model ANOVA to quantify individual variability. Statistically significant, systematic individual differences in the effects of sleep deprivation were observed, even when baseline differences were accounted for. The findings suggest that highly select populations may exhibit individual differences in vulnerability to performance impairment from sleep loss just as the general population does. Thus, the scientific and operational communities' reliance on group data as opposed to individual data may entail substantial misestimation of the impact of job-related stressors on safety and performance.

Seroprevalence of toxocariasis in hypereosinophilic individuals in Ahwaz, south-western Iran.

PubMed

Maraghi, S; Rafiei, A; Hajihossein, R; Sadjjadi, S M

2012-06-01

Eosinophilia in human peripheral blood is caused by different agents, including toxocariasis. The present study aimed to evaluate the prevalence of toxocariasis in hypereosinophilic individuals in the city of Ahwaz, located in south-western Iran, using enzyme-linked immunosorbent assay and Western blot techniques. Serum samples were examined from 100 individuals with peripheral blood eosinophilia and also from another 100 individuals without eosinophilia as the control group. In hypereosinophilic individuals seroprevalence antibodies against Toxocara were found in 19 (19%), of whom 12 (63.15%) were female and 7 (36.85%) were male. Positive sera were subsequently confirmed by Western blot. All of the observed bands ranged from 24 to 100 kDa. Antibodies against Toxocara were found in 1% of the control group, but were not confirmed by Western blot. The results showed significant differences between the frequency of infection within age and gender (P < 0.05); the highest prevalence of infection was observed in adults. Differences between the hypereosinophilic and healthy individuals, in terms of Toxocara infection frequency, also proved significant (P < 0.05).The present study thus confirmed the significant prevalence of toxocariasis as a hygienic problem among hypereosinophilic individuals in this area. It is, therefore, necessary to examine these individuals for toxocariasis.

Individual differences in the preferred neck-resting position of Caribbean flamingos (Phoenicopterus ruber).

PubMed

Anderson, Matthew J; Williams, Sarah A; O'Brien, Edward H

2009-01-01

When resting, flamingos often lay their heads along their backs. While in this position they must curve their necks to either the right or left of their midline. Observations of captive Caribbean flamingos at the Philadelphia Zoo (Philadelphia, PA, USA) were conducted in order to determine if individual birds would display consistent preferences in neck-resting position over multiple observations. While individual birds were shown to vary greatly in regards to the strength and direction of their preferences, a significant flock-level preference towards neck resting to the right was obtained. Analysis of individual flamingos revealed that 5 out of 17 birds displayed preferences that significantly differed from chance, with each of these birds preferring to rest their necks to the right. From the present data we can conclude that flamingos display behavioural laterality of neck-resting position at both the level of the group and that of the individual.

Predicting individual differences in decision-making process from signature movement styles: an illustrative study of leaders.

PubMed

Connors, Brenda L; Rende, Richard; Colton, Timothy J

2013-01-01

There has been a surge of interest in examining the utility of methods for capturing individual differences in decision-making style. We illustrate the potential offered by Movement Pattern Analysis (MPA), an observational methodology that has been used in business and by the US Department of Defense to record body movements that provide predictive insight into individual differences in decision-making motivations and actions. Twelve military officers participated in an intensive 2-h interview that permitted detailed and fine-grained observation and coding of signature movements by trained practitioners using MPA. Three months later, these subjects completed four hypothetical decision-making tasks in which the amount of information sought out before coming to a decision, as well as the time spent on the tasks, were under the partial control of the subject. A composite MPA indicator of how a person allocates decision-making actions and motivations to balance both Assertion (exertion of tangible movement effort on the environment to make something occur) and Perspective (through movements that support shaping in the body to perceive and create a suitable viewpoint for action) was highly correlated with the total number of information draws and total response time-individuals high on Assertion reached for less information and had faster response times than those high on Perspective. Discussion focuses on the utility of using movement-based observational measures to capture individual differences in decision-making style and the implications for application in applied settings geared toward investigations of experienced leaders and world statesmen where individuality rules the day.

Predicting individual differences in decision-making process from signature movement styles: an illustrative study of leaders

PubMed Central

Connors, Brenda L.; Rende, Richard; Colton, Timothy J.

2013-01-01

There has been a surge of interest in examining the utility of methods for capturing individual differences in decision-making style. We illustrate the potential offered by Movement Pattern Analysis (MPA), an observational methodology that has been used in business and by the US Department of Defense to record body movements that provide predictive insight into individual differences in decision-making motivations and actions. Twelve military officers participated in an intensive 2-h interview that permitted detailed and fine-grained observation and coding of signature movements by trained practitioners using MPA. Three months later, these subjects completed four hypothetical decision-making tasks in which the amount of information sought out before coming to a decision, as well as the time spent on the tasks, were under the partial control of the subject. A composite MPA indicator of how a person allocates decision-making actions and motivations to balance both Assertion (exertion of tangible movement effort on the environment to make something occur) and Perspective (through movements that support shaping in the body to perceive and create a suitable viewpoint for action) was highly correlated with the total number of information draws and total response time—individuals high on Assertion reached for less information and had faster response times than those high on Perspective. Discussion focuses on the utility of using movement-based observational measures to capture individual differences in decision-making style and the implications for application in applied settings geared toward investigations of experienced leaders and world statesmen where individuality rules the day. PMID:24069012

Shyness and boldness in pumpkinseed sunfish: individual differences are context-specific.

PubMed

Coleman; Wilson

1998-10-01

Natural selection often promotes a mix of behavioural phenotypes in a population. Adaptive variation in the propensity to take risks might explain individual differences in shyness and boldness in humans and other species. It is often implicitly assumed that shyness and boldness are general personality traits expressed across many situations. From the evolutionary standpoint, however, individual differences that are adaptive in one context (e.g. predator defence) may not be adaptive in other contexts (e.g. exploration of the physical environment or intraspecific social interactions). We measured the context specificity of shyness and boldness in a natural population of juvenile pumpkinseed sunfish, Lepomis gibbosus, by exposing the fish to a potentially threatening stimulus (a red-tipped metrestick extended towards the individual) and a nonthreatening stimulus (a novel food source). We also related these measures of shyness and boldness to behaviours observed during focal observations, both before and after the introduction of a predator (largemouth bass, Micropterus salmoides). Consistent individual differences were found within both contexts, but individual differences did not correlate across contexts. Furthermore, fish that were scored as intermediate in their response to the metrestick behaved most boldly as foragers and in response to the bass predators. These results suggest that shyness and boldness are context-specific and may not exist as a one-dimensional behavioural continuum even within a single context. Copyright 1998 The Association for the Study of Animal Behaviour.

Neuroanatomical and Symptomatic Sex Differences in Individuals at Clinical High Risk for Psychosis.

PubMed

Guma, Elisa; Devenyi, Gabriel A; Malla, Ashok; Shah, Jai; Chakravarty, M Mallar; Pruessner, Marita

2017-01-01

Sex differences have been widely observed in clinical presentation, functional outcome and neuroanatomy in individuals with a first-episode of psychosis, and chronic patients suffering from schizophrenia. However, little is known about sex differences in the high-risk stages for psychosis. The present study investigated sex differences in cortical and subcortical neuroanatomy in individuals at clinical high risk (CHR) for psychosis and healthy controls (CTL), and the relationship between anatomy and clinical symptoms in males at CHR. Magnetic resonance images were collected in 26 individuals at CHR (13 men) and 29 CTLs (15 men) to determine total and regional brain volumes and morphology, cortical thickness, and surface area (SA). Clinical symptoms were assessed with the brief psychiatric rating scale. Significant sex-by-diagnosis interactions were observed with opposite directions of effect in male and female CHR subjects relative to their same-sex controls in multiple cortical and subcortical areas. The right postcentral, left superior parietal, inferior parietal supramarginal, and angular gyri [<5% false discovery rate (FDR)] were thicker in male and thinner in female CHR subjects compared with their same-sex CTLs. The same pattern was observed in the right superior parietal gyrus SA at the regional and vertex level. Using a recently developed surface-based morphology pipeline, we observed sex-specific shape differences in the left hippocampus (<5% FDR) and amygdala (<10% FDR). Negative symptom burden was significantly higher in male compared with female CHR subjects ( p  = 0.04) and was positively associated with areal expansion of the left amygdala in males (<5% FDR). Some limitations of the study include the sample size, and data acquisition at 1.5 T. This study demonstrates neuroanatomical sex differences in CHR subjects, which may be associated with variations in symptomatology in men and women with psychotic symptoms.

Probabilistic reasoning under time pressure: an assessment in Italian, Spanish and English psychology undergraduates

NASA Astrophysics Data System (ADS)

Agus, M.; Hitchcott, P. K.; Penna, M. P.; Peró-Cebollero, M.; Guàrdia-Olmos, J.

2016-11-01

Many studies have investigated the features of probabilistic reasoning developed in relation to different formats of problem presentation, showing that it is affected by various individual and contextual factors. Incomplete understanding of the identity and role of these factors may explain the inconsistent evidence concerning the effect of problem presentation format. Thus, superior performance has sometimes been observed for graphically, rather than verbally, presented problems. The present study was undertaken to address this issue. Psychology undergraduates without any statistical expertise (N = 173 in Italy; N = 118 in Spain; N = 55 in England) were administered statistical problems in two formats (verbal-numerical and graphical-pictorial) under a condition of time pressure. Students also completed additional measures indexing several potentially relevant individual dimensions (statistical ability, statistical anxiety, attitudes towards statistics and confidence). Interestingly, a facilitatory effect of graphical presentation was observed in the Italian and Spanish samples but not in the English one. Significantly, the individual dimensions predicting statistical performance also differed between the samples, highlighting a different role of confidence. Hence, these findings confirm previous observations concerning problem presentation format while simultaneously highlighting the importance of individual dimensions.

Time-resolved metabolomics analysis of individual differences during the early stage of lipopolysaccharide-treated rats.

PubMed

Dai, Die; Gao, Yiqiao; Chen, Jiaqing; Huang, Yin; Zhang, Zunjian; Xu, Fengguo

2016-10-03

Lipopolysaccharide (LPS) can lead to uncontrollable cytokine production and eventually cause fatal sepsis syndrome. Individual toxicity difference of LPS has been widely reported. In our study we observed that two thirds of the rats (24/36) died at a given dose of LPS, while the rest (12/36) survived. Tracking the dynamic metabolic change in survival and non-survival rats in the early stage may reveal new system information to understand the inter-individual variation in response to LPS. As the time-resolved datasets are very complex and no single method can elucidate the problem clearly and comprehensively, the static and dynamic metabolomics methods were employed in combination as cross-validation. Intriguingly, some common results have been observed. Lipids were the main different metabolites between survival and non-survival rats in pre-dose serum and in the early stage of infection with LPS. The LPS treatment led to S-adenosly-methionine and total cysteine individual difference in early stage, and subsequent significant perturbations in energy metabolism and oxidative stress. Furthermore, cytokine profiles were analyzed to identify potential biological associations between cytokines and specific metabolites. Our collective findings may provide some heuristic guidance for elucidating the underlying mechanism of individual difference in LPS-mediated disease.

Measuring Attitudes That Bias Teacher Observation.

ERIC Educational Resources Information Center

Marston, Paul T.; Clements, Richard O.

It was hypothesized that individual differences in observer attitudes might affect the way observers code teacher behavior. A questionnaire assessing educational attitudes was given to 22 subjects who were trained on 3 classroom observation systems: the Flanders Interaction Analysis, the Classroom Observation Scales, and the Classroom Observation…

Gender and age related differences in foot morphology.

PubMed

Tomassoni, Daniele; Traini, Enea; Amenta, Francesco

2014-12-01

This study has assessed age-related changes of foot morphology for developing appropriate footwear with particular reference to the elderly. Anatomical parameters such as foot length, circumference and height and ankle length, circumference and height were assessed in a sample of males (n=577) and females (n=528) divided into three age groups. The groups included young-adult, aged between 20 and 25 years; adult, aged between 35 and 55 years; and old, aged between 65 and 70 years individuals. In terms of gender differences, in young-adult individuals the sex-related morphological differences observed, are just related to a significantly lower length of foot in females. In adult subjects morphological parameters investigated were significantly lower in females even after normalization for foot length. In old individuals, no differences of the parameters were found after normalization for foot length. Comparative analysis of morphometric data between young-adult and adult individuals revealed that the instep length was smaller in adults. The opposite was observed for the great toe and medial foot arch height. Length of ankle was higher in adult than in young-adult individuals, whereas ankle circumference and height were smaller. In old vs adult individuals foot circumference showed the most relevant age-related differences. Feet anatomy presents specific characteristics in different ages of life. The ideal footwear should take into account these characteristics. This is true primarily for the elderly for minimizing the risk of falls or of other problems related to inappropriate footwear. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Vacillating between Opposing Conceptions of Personhood: Individualism and Conformism in Turkish Educational Practices

ERIC Educational Resources Information Center

Ceyhan, Muge Ayan

2009-01-01

Based on one and a half years of participant observation at Bakis School, this article aims to explore two different sets of educational practices, one which seemingly promotes sameness, obedience and conformity, and the other difference, entrepreneurialism and individualism. By way of discussing the shifting cultural values, beliefs and…

Group therapy as a social context for aphasia recovery: a pilot, observational study in an acute rehabilitation hospital.

PubMed

Fama, Mackenzie E; Baron, Christine R; Hatfield, Brooke; Turkeltaub, Peter E

2016-08-01

Individuals with aphasia often receive therapy from a speech-language pathologist during acute rehabilitation. The literature demonstrates that group-based therapy provides a natural, social environment for language rehabilitation in mild-moderate and/or chronic aphasia; however, the communication of persons with acute, severe non-fluent aphasia during group treatment has not been fully explored. This observational study investigated patient communication during acute rehabilitation. The primary objective was to determine whether participants initiate more communication during group therapy sessions when compared to individual therapy sessions. Ten participants with severe non-fluent aphasia were observed during one individual and one group session during their stay in an acute, inpatient rehabilitation facility. Communicative initiations were tallied and categorized based on type, target, and purpose. Participants initiated communication more often during group sessions than during individual sessions. During groups, participants used more vocalizations and facial expressions to communicate, and the purpose was more often for social closeness than in individual sessions. Participants produced fewer different, real words in group vs. individual sessions, but other measures of communication skill did not differ significantly between the two settings. In the aphasia group treatment described in this study, participants initiated more communication, with greater diversity of expressive modalities and more varied communicative purposes. Participants in group therapy also showed an increased tendency to communicate for the purpose of social closeness. These findings suggest that there are important differences in the communication of patients participating in group vs. individual speech therapy for treatment of acute, severe non-fluent aphasia.

In others' shoes: do individual differences in empathy and theory of mind shape social preferences?

PubMed

Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri

2014-01-01

Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person.

The 'whys' and 'whens' of individual differences in thinking biases.

PubMed

De Neys, Wim; Bonnefon, Jean-François

2013-04-01

Although human thinking is often biased, some individuals are less susceptible to biases than others. These individual differences have been at the forefront of thinking research for more than a decade. We organize the literature in three key accounts (storage, monitoring, and inhibition failure) and propose that a critical but overlooked question concerns the time point at which individual variance arises: do biased and unbiased reasoners take different paths early on in the reasoning process or is the observed variance late to arise? We discuss how this focus on the 'whens' suggests that individual differences in thinking biases are less profound than traditionally assumed, in the sense that they might typically arise at a later stage of the reasoning process. Copyright © 2013 Elsevier Ltd. All rights reserved.

Predicting risk in space: Genetic markers for differential vulnerability to sleep restriction

NASA Astrophysics Data System (ADS)

Goel, Namni; Dinges, David F.

2012-08-01

Several laboratories have found large, highly reliable individual differences in the magnitude of cognitive performance, fatigue and sleepiness, and sleep homeostatic vulnerability to acute total sleep deprivation and to chronic sleep restriction in healthy adults. Such individual differences in neurobehavioral performance are also observed in space flight as a result of sleep loss. The reasons for these stable phenotypic differential vulnerabilities are unknown: such differences are not yet accounted for by demographic factors, IQ or sleep need, and moreover, psychometric scales do not predict those individuals cognitively vulnerable to sleep loss. The stable, trait-like (phenotypic) inter-individual differences observed in response to sleep loss—with intraclass correlation coefficients accounting for 58-92% of the variance in neurobehavioral measures—point to an underlying genetic component. To this end, we utilized multi-day highly controlled laboratory studies to investigate the role of various common candidate gene variants—each independently—in relation to cumulative neurobehavioral and sleep homeostatic responses to sleep restriction. These data suggest that common genetic variations (polymorphisms) involved in sleep-wake, circadian, and cognitive regulation may serve as markers for prediction of inter-individual differences in sleep homeostatic and neurobehavioral vulnerability to sleep restriction in healthy adults. Identification of genetic predictors of differential vulnerability to sleep restriction—as determined from candidate gene studies—will help identify astronauts most in need of fatigue countermeasures in space flight and inform medical standards for obtaining adequate sleep in space. This review summarizes individual differences in neurobehavioral vulnerability to sleep deprivation and ongoing genetic efforts to identify markers of such differences.

Heart rate modulation in bystanding geese watching social and non-social events

PubMed Central

Wascher, Claudia A.F; Scheiber, Isabella B.R; Kotrschal, Kurt

2008-01-01

Simply observing other individuals interacting has been shown to affect subsequent behaviour and also hormones in ‘bystander’ individuals. However, immediate physiological responses of an observer have been hardly investigated. Here we present results on individuals' heart rate (HR) responses during various situations, which occur regularly in a flock of greylag geese (Anser anser, e.g. agonistic encounters, vehicles passing by). We recorded simultaneously HR and behaviour of 21 semi-tame free-roaming geese, equipped with fully implanted transmitters. We considered 304 social and 81 non-social events during which the focal individuals did not respond behaviourally. Independent of the spatial distance to the event, these HR responses were significantly greater in social contexts (e.g. departing or landing geese, agonistic interactions) than in non-social situations (e.g. vehicles passing by, thunder). Focal individuals showed a significantly higher maximum HR as well as a greater HR increase in response to agonistic interactions, in which the pair partner or a family member was involved, as compared with a non-affiliated goose. Also, HR was significantly higher when the bystander watched non-affiliated geese interacting, which were higher ranking than the focal. We conclude that these differences are due to different relevance of the recorded events for the focal individual, depending on the individuals involved in the observed interaction. PMID:18430645

Assessing pig body language: agreement and consistency between pig farmers, veterinarians, and animal activists.

PubMed

Wemelsfelder, F; Hunter, A E; Paul, E S; Lawrence, A B

2012-10-01

This study investigates the interobserver and intraobserver reliability of qualitative behavior assessments (QBA) of individual pigs by 3 observer groups selected for their diverging backgrounds, experience, and views of pigs. Qualitative behavior assessment is a "whole animal" assessment approach that characterizes the demeanor of an animal as an expressive body language, using descriptors such as relaxed, anxious, or content. This paper addresses the concern that use of such descriptors in animal science may be prone to distortion by observer-related bias. Using a free-choice profiling methodology, 12 pig farmers, 10 large animal veterinarians, and 10 animal protectionists were instructed to describe and score the behavioral expressions of 10 individual pigs (sus scrofa) in 2 repeat sets of 10 video clips, showing these pigs in interaction with a human female. They were also asked to fill in a questionnaire gauging their experiences with and views on pigs. Pig scores were analyzed with generalized procrustes analysis and effect of treatment on these scores with ANOVA. Questionnaire scores were analyzed with a χ(2) test or ANOVA. Observers achieved consensus both within and among observer groups (P < 0.001), identifying 2 main dimensions of pig expression (dim1: playful/confident-cautious/timid; dim2: aggressive/nervous-relaxed/bored), on which pig scores for different observer groups were highly correlated (pearson r > 0.90). The 3 groups also repeated their assessments of individual pigs with high precision (r > 0.85). Animal protectionists used a wider quantitative range in scoring individual pigs on dimension 2 than the other groups (P < 0.001); however, this difference did not distort the strong overall consistency of characterizations by observers of individual pigs. Questionnaire results indicated observer groups to differ in various ways, such as daily and lifetime contact with pigs (P < 0.001), some aspects of affection and empathy for pigs (P < 0.05), and confidence in the validity of personal QBA descriptors (P < 0.02). The main finding of this study is that despite such differences in background and outlook, the 3 observer groups showed high interobserver and intraobserver reliability in their characterizations of pig body language. This supports the empirical nature of QBA in context of the wider anthropomorphism debate.

Accounting for taste: individual differences in preference for harmony.

PubMed

Palmer, Stephen E; Griscom, William S

2013-06-01

Although empirical research on aesthetics has had some success in explaining the average preferences of groups of observers, relatively little is known about individual differences in preference, and especially about how such differences might covary across different domains. In this study, we identified a new factor underlying aesthetic response-preference for harmonious stimuli-and examined how it varies over four domains (color, shape, spatial location, and music) across individuals with different levels of training in art and music. We found that individual preferences for harmony are strongly correlated across all four dimensions tested and decrease consistently with training in the relevant aesthetic domains. Confirmatory factor analysis revealed that cross-domain preference for harmony is well-represented as a single, unified factor, with effects separate from those of training and of common personality measures.

Individual Differences in Toddlers' Prosociality: Experiences in Early Relationships Explain Variability in Prosocial Behavior

ERIC Educational Resources Information Center

Newton, Emily K.; Thompson, Ross A.; Goodman, Miranda

2016-01-01

Latent class logistic regression analysis was used to investigate sources of individual differences in profiles of prosocial behavior. Eighty-seven 18-month-olds were observed in tasks assessing sharing with a neutral adult, instrumentally helping a neutral adult, and instrumentally helping a sad adult. Maternal mental state language (MSL) and…

In Others' Shoes: Do Individual Differences in Empathy and Theory of Mind Shape Social Preferences?

PubMed Central

Artinger, Florian; Exadaktylos, Filippos; Koppel, Hannes; Sääksvuori, Lauri

2014-01-01

Abundant evidence across the behavioral and social sciences suggests that there are substantial individual differences in pro-social behavior. However, little is known about the psychological mechanisms that underlie social preferences. This paper investigates whether empathy and Theory of Mind shape individual differences in pro-social behavior as conventionally observed in neutrally framed social science experiments. Our results show that individual differences in the capacity for empathy do not shape social preferences. The results qualify the role of Theory of Mind in strategic interaction. We do not only show that fair individuals exhibit more accurate beliefs about the behavior of others but that Theory of Mind can be effectively used to pursue both self-interest and pro-social goals depending on the principle objectives of a person. PMID:24743312

People with stroke spend more time in active task practice, but similar time in walking practice, when physiotherapy rehabilitation is provided in circuit classes compared to individual therapy sessions: an observational study.

PubMed

English, Coralie; Hillier, Susan; Kaur, Gurpreet; Hundertmark, Laura

2014-03-01

Do people with stroke spend more time in active task practice during circuit class therapy sessions versus individual physiotherapy sessions? Do people with stroke practise different tasks during circuit class therapy sessions versus individual physiotherapy sessions? Prospective, observational study. Twenty-nine people with stroke in inpatient rehabilitation settings. Individual therapy sessions and circuit class therapy sessions provided within a larger randomised controlled trial. Seventy-nine therapy sessions were video-recorded and the footage was analysed for time spent engaged in various categories of activity. In a subsample of 28 videos, the number of steps taken by people with stroke per therapy session was counted. Circuit class therapy sessions were of a longer duration (mean difference 38.0minutes, 95% CI 29.9 to 46.1), and participants spent more time engaged in active task practice (mean difference 23.8minutes, 95% CI 16.1 to 31.4) compared with individual sessions. A greater percentage of time in circuit class therapy sessions was spent practising tasks in sitting (mean difference 5.3%, 95% CI 2.4 to 8.2) and in sit-to-stand practice (mean difference 2.7%, 95% CI 1.4 to 4.1), and a lower percentage of time in walking practice (mean difference 19.1%, 95% CI 10.0 to 28.1) compared with individual sessions. PARTICIPANTS took an average of 371 steps (SD 418) during therapy sessions and this did not differ significantly between group and individual sessions. People with stroke spent more time in active task practice, but a similar amount of time in walking practice when physiotherapy was offered in circuit class therapy sessions versus individual therapy sessions. There is a need for effective strategies to increase the amount of walking practice during physiotherapy sessions for people after stroke. Copyright © 2014 Australian Physiotherapy Association. Published by Elsevier B.V. All rights reserved.

Microbiome Heterogeneity Characterizing Intestinal Tissue and Inflammatory Bowel Disease Phenotype.

PubMed

Tyler, Andrea D; Kirsch, Richard; Milgrom, Raquel; Stempak, Joanne M; Kabakchiev, Boyko; Silverberg, Mark S

2016-04-01

Inflammatory bowel disease has been associated with differential abundance of numerous organisms when compared to healthy controls (HCs); however, few studies have investigated variability in the microbiome across intestinal locations and how this variability might be related to disease location and phenotype. In this study, we have analyzed the microbiome of a large cohort of individuals recruited at Mount Sinai Hospital in Toronto, Canada. Biopsies were taken from subjects with Crohn's disease, ulcerative colitis, and HC, and also individuals having undergone ileal pouch-anal anastomosis for treatment of ulcerative colitis or familial adenomatous polyposis. Microbial 16S rRNA was sequenced using the Illumina MiSeq platform. We observed a great deal of variability in the microbiome characterizing different sampling locations. Samples from pouch and afferent limb were comparable in microbial composition. When comparing sigmoid and terminal ileum samples, more differences were observed. The greatest number of differentially abundant microbes was observed when comparing either pouch or afferent limb samples to sigmoid or terminal ileum. Despite these differences, we were able to observe modest microbial variability between inflammatory bowel disease phenotypes and HCs, even when controlling for sampling location and additional experimental factors. Most detected associations were observed between HCs and Crohn's disease, with decreases in specific genera in the families Ruminococcaceae and Lachnospiraceae characterizing tissue samples from individuals with Crohn's disease. This study highlights important considerations when analyzing the composition of the microbiome and also provides useful insight into differences in the microbiome characterizing these seemingly related phenotypes.

On the importance of considering heterogeneity in witnesses' competence levels when reconstructing crimes from multiple witness testimonies.

PubMed

Waubert de Puiseau, Berenike; Greving, Sven; Aßfalg, André; Musch, Jochen

2017-09-01

Aggregating information across multiple testimonies may improve crime reconstructions. However, different aggregation methods are available, and research on which method is best suited for aggregating multiple observations is lacking. Furthermore, little is known about how variance in the accuracy of individual testimonies impacts the performance of competing aggregation procedures. We investigated the superiority of aggregation-based crime reconstructions involving multiple individual testimonies and whether this superiority varied as a function of the number of witnesses and the degree of heterogeneity in witnesses' ability to accurately report their observations. Moreover, we examined whether heterogeneity in competence levels differentially affected the relative accuracy of two aggregation procedures: a simple majority rule, which ignores individual differences, and the more complex general Condorcet model (Romney et al., Am Anthropol 88(2):313-338, 1986; Batchelder and Romney, Psychometrika 53(1):71-92, 1988), which takes into account differences in competence between individuals. 121 participants viewed a simulated crime and subsequently answered 128 true/false questions about the crime. We experimentally generated groups of witnesses with homogeneous or heterogeneous competences. Both the majority rule and the general Condorcet model provided more accurate reconstructions of the observed crime than individual testimonies. The superiority of aggregated crime reconstructions involving multiple individual testimonies increased with an increasing number of witnesses. Crime reconstructions were most accurate when competences were heterogeneous and aggregation was based on the general Condorcet model. We argue that a formal aggregation should be considered more often when eyewitness testimonies have to be assessed and that the general Condorcet model provides a good framework for such aggregations.

Propagation of New Innovations: An Approach to Classify Human Behavior and Movement from Available Social Network Data

NASA Technical Reports Server (NTRS)

Mahmud, Faisal; Samiul, Hasan

2010-01-01

It is interesting to observe new innovations, products, or ideas propagating into the society. One important factor of this propagation is the role of individual's social network; while another factor is individual's activities. In this paper, an approach will be made to analyze the propagation of different ideas in a popular social network. Individuals' responses to different activities in the network will be analyzed. The properties of network will also be investigated for successful propagation of innovations.

Beyond Self-Report: Emerging Methods for Capturing Individual Differences in Decision-Making Process

PubMed Central

Connors, Brenda L.; Rende, Richard; Colton, Timothy J.

2016-01-01

People vary in the way in which they approach decision-making, which impacts real-world behavior. There has been a surge of interest in moving beyond reliance on self-report measures to capture such individual differences. Particular emphasis has been placed on devising and applying a range of methodologies that include experimental, neuroscience, and observational paradigms. This paper provides a selective review of recent studies that illustrate the methods and yield of these approaches in terms of generating a deeper understanding of decision-making style and the notable differences that can be found across individuals. PMID:26973589

Beyond Self-Report: Emerging Methods for Capturing Individual Differences in Decision-Making Process.

PubMed

Connors, Brenda L; Rende, Richard; Colton, Timothy J

2016-01-01

People vary in the way in which they approach decision-making, which impacts real-world behavior. There has been a surge of interest in moving beyond reliance on self-report measures to capture such individual differences. Particular emphasis has been placed on devising and applying a range of methodologies that include experimental, neuroscience, and observational paradigms. This paper provides a selective review of recent studies that illustrate the methods and yield of these approaches in terms of generating a deeper understanding of decision-making style and the notable differences that can be found across individuals.

The Effect of Using Self-Monitoring Strategies in Social Studies Course on Self-Monitoring, Self-Regulation and Academic Achievement

ERIC Educational Resources Information Center

Arslantas, Suleyman; Kurnaz, Ahmet

2017-01-01

In an attempt to clarify the behavioral differences and a dimension of the individual's metacognitive processes, Snyder introduced the "Self-Monitoring Theory" in 1974. According to the theory, individuals differ in the extent to which they control their self-presentation in social interactions. Some people can observe and control their…

Decay, Transfer, and the Reacquisition of a Complex Skill: An Investigation of Practice Schedules, Observational Rehearsal, and Individual Differences

DTIC Science & Technology

2007-12-01

Academic Press. Battig, W. F. (1979). The flexibility of human memory. In L. S. Cermak & F. I. Craik (Eds.), Levels of processing in human memory...with retention, transfer, and reacquisition, overall levels of prediction were relatively weak, especially for transfer. Differences in motivation...Although some individual differences (e.g., self-efficacy) were consistently associated with retention, transfer, and reacquisition, overall levels

The Action Observation System when Observing Hand Actions in Autism and Typical Development.

PubMed

Pokorny, Jennifer J; Hatt, Naomi V; Colombi, Costanza; Vivanti, Giacomo; Rogers, Sally J; Rivera, Susan M

2015-06-01

Social impairments in individuals with autism spectrum disorders (ASD) may be in part due to difficulty perceiving and recognizing the actions of others. Evidence from imitation studies, which involves both observation and execution of an action, suggests differences, in individuals with ASD, between the ability to imitate goal-directed actions involving objects (transitive actions) and the ability to imitate actions that do not involve objects (intransitive actions). In the present study, we examined whether there were differences in how ASD adolescents encoded transitive and intransitive actions compared to typically developing (TD) adolescents, by having participants view videos of a hand reaching across a screen toward an object or to where an object would be while functional magnetic resonance images were collected. Analyses focused on areas within the action observation network (AON), which is activated during the observation of actions performed by others. We hypothesized that the AON would differentiate transitive from intransitive actions only in the ASD group. However, results revealed that object presence modulated activity in the right inferior frontal gyrus and supramarginal gyrus of the TD group, a differentiation that was not seen in the ASD group. Furthermore, there were no significant group differences between the TD and ASD groups in any of the conditions. This suggests that there is not a global deficit of the AON in individuals with ASD while observing transitive and intransitive actions. © 2015 International Society for Autism Research, Wiley Periodicals, Inc.

Predicting variations of perceptual performance across individuals from neural activity using pattern classifiers.

PubMed

Das, Koel; Giesbrecht, Barry; Eckstein, Miguel P

2010-07-15

Within the past decade computational approaches adopted from the field of machine learning have provided neuroscientists with powerful new tools for analyzing neural data. For instance, previous studies have applied pattern classification algorithms to electroencephalography data to predict the category of presented visual stimuli, human observer decision choices and task difficulty. Here, we quantitatively compare the ability of pattern classifiers and three ERP metrics (peak amplitude, mean amplitude, and onset latency of the face-selective N170) to predict variations across individuals' behavioral performance in a difficult perceptual task identifying images of faces and cars embedded in noise. We investigate three different pattern classifiers (Classwise Principal Component Analysis, CPCA; Linear Discriminant Analysis, LDA; and Support Vector Machine, SVM), five training methods differing in the selection of training data sets and three analyses procedures for the ERP measures. We show that all three pattern classifier algorithms surpass traditional ERP measurements in their ability to predict individual differences in performance. Although the differences across pattern classifiers were not large, the CPCA method with training data sets restricted to EEG activity for trials in which observers expressed high confidence about their decisions performed the highest at predicting perceptual performance of observers. We also show that the neural activity predicting the performance across individuals was distributed through time starting at 120ms, and unlike the face-selective ERP response, sustained for more than 400ms after stimulus presentation, indicating that both early and late components contain information correlated with observers' behavioral performance. Together, our results further demonstrate the potential of pattern classifiers compared to more traditional ERP techniques as an analysis tool for modeling spatiotemporal dynamics of the human brain and relating neural activity to behavior. Copyright 2010 Elsevier Inc. All rights reserved.

Dietary intake of energy, nutrients and water in elderly people living at home or in nursing home.

PubMed

Engelheart, S; Akner, G

2015-03-01

There is a lack of detailed information on dietary intake in elderly people at an individual level, which is crucial for improvement of nutritional support. The aim of this study was to investigate the dietary intake in elderly people in two types of living situations. Observational study, analysing prospective data. The dietary intake was studied in elderly people living at home or in nursing home, in different cities of Sweden. A total of 264 elderly people (mean age 84) participated in the observational study. Dietary intake was measured using weighed food records and food diaries, comparing females and males. The observed dietary intake was related to Recommended intake and Lower intake level. All dietary intake and patient characteristic variables showed large individual differences (ranges). We found no significant differences (p>0.05) between those living at home and nursing home residents regarding the average intake of energy, protein and water when expressed as total intake per kg of body weight. A very low daily intake of energy (<20 kcal/kg body weight/day) was observed in 16% of the participants. For vitamin D and iron, 19% and 15%, respectively, had intakes below the Lower intake level. There was no correlation between intake of energy, protein or water and resident characteristics such as age, autonomy, morbidity, nutritional state or cognition. The large individual differences (ranges) in energy, nutrients and water show that the use of mean values when analysing dietary intake data from elderly people is misleading. From a clinical perspective it is more important to consider the individual intake of energy, nutrients and water. Ageism is intrinsic in the realm of 'averageology'.

Storyline Visualizations of Eye Tracking of Movie Viewing

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

Balint, John T.; Arendt, Dustin L.; Blaha, Leslie M.

Storyline visualizations offer an approach that promises to capture the spatio-temporal characteristics of individual observers and simultaneously illustrate emerging group behaviors. We develop a visual analytics approach to parsing, aligning, and clustering fixation sequences from eye tracking data. Visualization of the results captures the similarities and differences across a group of observers performing a common task. We apply our storyline approach to visualize gaze patterns of people watching dynamic movie clips. Storylines mitigate some of the shortcomings of existent spatio-temporal visualization techniques and, importantly, continue to highlight individual observer behavioral dynamics.

Serum copper and zinc concentrations in a representative sample of the Canarian population.

PubMed

Díaz Romero, Carlos; Henríquez Sánchez, Patricia; López Blanco, Félix; Rodríguez Rodríguez, Elena; Serra Majem, Lluis

2002-01-01

Serum copper (Cu) and zinc (Zn) concentrations of 395 individuals (187 males + 208 females) living in Canary Islands were determined by flame atomic absorption spectrometry. The mean copper and zinc concentrations were 1.10 +/- 0.25 mg/L and 1.16 +/- 0.52 mg/L respectively. Our data were similar to other data published in other Spanish regions. Individuals from Lanzarote presented a mean Cu and Zn concentrations higher (p < 0.05) than individuals from the rest of islands; Individuals from EL Hierro showed the lowest (p < 0.05) mean Zn concentration. These differences could be attributed a differences in Cu and Zn contents of soil and/or differences in dietary habits of the populations. The mean serum Cu concentration in females was higher (p < 0.05) than in males, however serum Zn concentration did not vary with the sex of the subjects. No relation to socio-economic status and educational level were found with respect to the serum Cu and Zn concentrations. The serum Cu concentration varied with age of individuals, observing the highest (p < 0.05) Cu concentration in the 20-30 year old interval. A higher serum Cu concentration in females within 20-30 year old interval was observed. This could be due to a higher use of oral contraceptives or to the higher number of pregnancies. Boys (younger than 15) showed a decrease (p < 0.05) of the serum Cu concentration with age. The mean Zn concentrations in serum did not change (p > 0.05) among the different age intervals. No clear trends in the serum Cu and Zn concentrations were observed when drinking and smoking habits were considered. The increase of physical exercise reduced (p < 0.05) the serum Cu concentrations.

Diagnosing prosopagnosia in East Asian individuals: Norms for the Cambridge Face Memory Test-Chinese.

PubMed

McKone, Elinor; Wan, Lulu; Robbins, Rachel; Crookes, Kate; Liu, Jia

2017-07-01

The Cambridge Face Memory Test (CFMT) is widely accepted as providing a valid and reliable tool in diagnosing prosopagnosia (inability to recognize people's faces). Previously, large-sample norms have been available only for Caucasian-face versions, suitable for diagnosis in Caucasian observers. These are invalid for observers of different races due to potentially severe other-race effects. Here, we provide large-sample norms (N = 306) for East Asian observers on an Asian-face version (CFMT-Chinese). We also demonstrate methodological suitability of the CFMT-Chinese for prosopagnosia diagnosis (high internal reliability, approximately normal distribution, norm-score range sufficiently far above chance). Additional findings were a female advantage on mean performance, plus a difference between participants living in the East (China) or the West (international students, second-generation children of immigrants), which we suggest might reflect personality differences associated with willingness to emigrate. Finally, we demonstrate suitability of the CFMT-Chinese for individual differences studies that use correlations within the normal range.

Individual Differences in Verbal Working Memory Underlie a Tradeoff between Semantic and Structural Processing Difficulty during Language Comprehension: An ERP Investigation

ERIC Educational Resources Information Center

Kim, Albert E.; Oines, Leif; Miyake, Akira

2018-01-01

This study investigated the processes reflected in the widely observed N400 and P600 event-related potential (ERP) effects and tested the hypothesis that the N400 and P600 effects are functionally linked in a tradeoff relationship, constrained in part by individual differences in cognitive ability. Sixty participants read sentences, and ERP…

Estimating Genetic Ancestry Proportions from Faces

PubMed Central

Klimentidis, Yann C.; Shriver, Mark D.

2009-01-01

Ethnicity can be a means by which people identify themselves and others. This type of identification mediates many kinds of social interactions and may reflect adaptations to a long history of group living in humans. Recent admixture in the US between groups from different continents, and the historically strong emphasis on phenotypic differences between members of these groups, presents an opportunity to examine the degree of concordance between estimates of group membership based on genetic markers and on visually-based estimates of facial features. We first measured the degree of Native American, European, African and East Asian genetic admixture in a sample of 14 self-identified Hispanic individuals, chosen to cover a broad range of Native American and European genetic admixture proportions. We showed frontal and side-view photographs of the 14 individuals to 241 subjects living in New Mexico, and asked them to estimate the degree of NA admixture for each individual. We assess the overall concordance for each observer based on an aggregated measure of the difference between the observer and the genetic estimates. We find that observers reach a significantly higher degree of concordance than expected by chance, and that the degree of concordance as well as the direction of the discrepancy in estimates differs based on the ethnicity of the observer, but not on the observers' age or sex. This study highlights the potentially high degree of discordance between physical appearance and genetic measures of ethnicity, as well as how perceptions of ethnic affiliation are context-specific. We compare our findings to those of previous studies and discuss their implications. PMID:19223962

The effect of wheelchair propulsion style on changes in time spent in extreme wrist orientations after a bout of fatiguing propulsion.

PubMed

Zukowski, Lisa A; Hass, Chris J; Shechtman, Orit; Christou, Evangelos A; Tillman, Mark D

2017-10-01

This study compared how wheelchair propulsion styles affect changes in percentage of time spent in extreme wrist orientations, which have been associated with median nerve injury, after a fatiguing bout of propulsion. Twenty novice, non-disabled adult males learned arcing (ARC) and semicircular (SEMI) propulsion styles and utilised each to perform a wheelchair fatigue protocol. ARC and SEMI did not significantly differ in terms of changes after the fatigue protocol in percentage of time spent in extreme flexion/extension or radial/ulnar deviation at the push phase beginning or end. A pattern was observed, although not significant, of greater increases in percentage of time spent in extreme wrist extension and ulnar deviation during the push phase beginning and ulnar deviation during the push phase end while utilising SEMI relative to ARC. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles. Practitioner Summary: How wheelchair propulsion styles change with fatigue in terms of extreme wrist orientations was examined. This study evinces that individual differences are greater than observed changes in extreme wrist orientations for both propulsion styles and point towards the need for future research on individual differences utilising propulsion styles.

Construct validity of the individual work performance questionnaire.

PubMed

Koopmans, Linda; Bernaards, Claire M; Hildebrandt, Vincent H; de Vet, Henrica C W; van der Beek, Allard J

2014-03-01

To examine the construct validity of the Individual Work Performance Questionnaire (IWPQ). A total of 1424 Dutch workers from three occupational sectors (blue, pink, and white collar) participated in the study. First, IWPQ scores were correlated with related constructs (convergent validity). Second, differences between known groups were tested (discriminative validity). First, IWPQ scores correlated weakly to moderately with absolute and relative presenteeism, and work engagement. Second, significant differences in IWPQ scores were observed for workers differing in job satisfaction, and workers differing in health. Overall, the results indicate acceptable construct validity of the IWPQ. Researchers are provided with a reliable and valid instrument to measure individual work performance comprehensively and generically, among workers from different occupational sectors, with and without health problems.

Contemporary divergence in early life history in grayling (Thymallus thymallus).

PubMed

Thomassen, Gaute; Barson, Nicola J; Haugen, Thrond O; Vøllestad, L Asbjørn

2011-12-13

Following colonization of new habitats and subsequent selection, adaptation to environmental conditions might be expected to be rapid. In a mountain lake in Norway, Lesjaskogsvatnet, more than 20 distinct spawning demes of grayling have been established since the lake was colonized, some 20-25 generations ago. The demes spawn in tributaries consistently exhibiting either colder or warmer temperature conditions during spawning in spring and subsequent early development during early summer. In order to explore the degree of temperature-related divergence in early development, a multi-temperature common-garden experiment was performed on embryos from four different demes experiencing different spring temperatures. Early developmental characters were measured to test if individuals from the four demes respond differently to the treatment temperatures. There was clear evidence of among-deme differences (genotype - environment interactions) in larval growth and yolk-to-body-size conversion efficiency. Under the cold treatment regime, larval growth rates were highest for individuals belonging to cold streams. Individuals from warm streams had the highest yolk-consumption rate under cold conditions. As a consequence, yolk-to-body-mass conversion efficiency was highest for cold-deme individuals under cold conditions. As we observed response parallelism between individuals from demes belonging to similar thermal groups for these traits, some of the differentiation seems likely to result from local adaptation The observed differences in length at age during early larval development most likely have a genetic component, even though both directional and random processes are likely to have influenced evolutionary change in the demes under study.

Flustered and faithful: embarrassment as a signal of prosociality.

PubMed

Feinberg, Matthew; Willer, Robb; Keltner, Dacher

2012-01-01

Although individuals experience embarrassment as an unpleasant, negative emotion, the authors argue that expressions of embarrassment serve vital social functions, signaling the embarrassed individual's prosociality and fostering trust. Extending past research on embarrassment as a nonverbal apology and appeasement gesture, the authors demonstrate that observers recognize the expression of embarrassment as a signal of prosociality and commitment to social relationships. In turn, observers respond with affiliative behaviors toward the signaler, including greater trust and desire to affiliate with the embarrassed individual. Five studies tested these hypotheses and ruled out alternative explanations. Study 1 demonstrated that individuals who are more embarrassable also reported greater prosociality and behaved more generously than their less embarrassable counterparts. Results of Studies 2-5 revealed that observers rated embarrassed targets as being more prosocial and less antisocial relative to targets who displayed either a different emotion or no emotion. In addition, observers were more willing to give resources and express a desire to affiliate with these targets, and these effects were mediated by perceptions of the targets as prosocial.

Extrapunitive and intropunitive individuals activate different parts of the prefrontal cortex under an ego-blocking frustration.

PubMed

Minamoto, Takehiro; Osaka, Mariko; Yaoi, Ken; Osaka, Naoyuki

2014-01-01

Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation.

The Effect of Early Visual Deprivation on the Neural Bases of Auditory Processing.

PubMed

Guerreiro, Maria J S; Putzar, Lisa; Röder, Brigitte

2016-02-03

Transient congenital visual deprivation affects visual and multisensory processing. In contrast, the extent to which it affects auditory processing has not been investigated systematically. Research in permanently blind individuals has revealed brain reorganization during auditory processing, involving both intramodal and crossmodal plasticity. The present study investigated the effect of transient congenital visual deprivation on the neural bases of auditory processing in humans. Cataract-reversal individuals and normally sighted controls performed a speech-in-noise task while undergoing functional magnetic resonance imaging. Although there were no behavioral group differences, groups differed in auditory cortical responses: in the normally sighted group, auditory cortex activation increased with increasing noise level, whereas in the cataract-reversal group, no activation difference was observed across noise levels. An auditory activation of visual cortex was not observed at the group level in cataract-reversal individuals. The present data suggest prevailing auditory processing advantages after transient congenital visual deprivation, even many years after sight restoration. The present study demonstrates that people whose sight was restored after a transient period of congenital blindness show more efficient cortical processing of auditory stimuli (here speech), similarly to what has been observed in congenitally permanently blind individuals. These results underscore the importance of early sensory experience in permanently shaping brain function. Copyright © 2016 the authors 0270-6474/16/361620-11$15.00/0.

Individual differences in behavioural plasticities.

PubMed

Stamps, Judy A

2016-05-01

Interest in individual differences in animal behavioural plasticities has surged in recent years, but research in this area has been hampered by semantic confusion as different investigators use the same terms (e.g. plasticity, flexibility, responsiveness) to refer to different phenomena. The first goal of this review is to suggest a framework for categorizing the many different types of behavioural plasticities, describe examples of each, and indicate why using reversibility as a criterion for categorizing behavioural plasticities is problematic. This framework is then used to address a number of timely questions about individual differences in behavioural plasticities. One set of questions concerns the experimental designs that can be used to study individual differences in various types of behavioural plasticities. Although within-individual designs are the default option for empirical studies of many types of behavioural plasticities, in some situations (e.g. when experience at an early age affects the behaviour expressed at subsequent ages), 'replicate individual' designs can provide useful insights into individual differences in behavioural plasticities. To date, researchers using within-individual and replicate individual designs have documented individual differences in all of the major categories of behavioural plasticities described herein. Another important question is whether and how different types of behavioural plasticities are related to one another. Currently there is empirical evidence that many behavioural plasticities [e.g. contextual plasticity, learning rates, IIV (intra-individual variability), endogenous plasticities, ontogenetic plasticities) can themselves vary as a function of experiences earlier in life, that is, many types of behavioural plasticity are themselves developmentally plastic. These findings support the assumption that differences among individuals in prior experiences may contribute to individual differences in behavioural plasticities observed at a given age. Several authors have predicted correlations across individuals between different types of behavioural plasticities, i.e. that some individuals will be generally more plastic than others. However, empirical support for most of these predictions, including indirect evidence from studies of relationships between personality traits and plasticities, is currently sparse and equivocal. The final section of this review suggests how an appreciation of the similarities and differences between different types of behavioural plasticities may help theoreticians formulate testable models to explain the evolution of individual differences in behavioural plasticities and the evolutionary and ecological consequences of individual differences in behavioural plasticities. © 2015 Cambridge Philosophical Society.

The Origins of Individual Differences in How Learning Is Expressed in Rats: A General-Process Perspective

PubMed Central

2016-01-01

Laboratory rats can exhibit marked, qualitative individual differences in the form of acquired behaviors. For example, when exposed to a signal-reinforcer relationship some rats show marked and consistent changes in sign-tracking (interacting with the signal; e.g., a lever) and others show marked and consistent changes in goal-tracking (interacting with the location of the predicted reinforcer; e.g., the food well). Here, stable individual differences in rats’ sign-tracking and goal-tracking emerged over the course of training, but these differences did not generalize across different signal-reinforcer relationships (Experiment 1). This selectivity suggests that individual differences in sign- and goal-tracking reflect differences in the value placed on individual reinforcers. Two findings provide direct support for this interpretation: the palatability of a reinforcer (as measured by an analysis of lick-cluster size) was positively correlated with goal-tracking (and negatively correlated with sign-tracking); and sating rats with a reinforcer affected goal-tracking but not sign-tracking (Experiment 2). These results indicate that the observed individual differences in sign- and goal-tracking behavior arise from the interaction between the palatability or value of the reinforcer and processes of association as opposed to dispositional differences (e.g., in sensory processes, “temperament,” or response repertoire). PMID:27732045

A visual tristimulus projection colorimeter.

PubMed

Valberg, A

1971-01-01

Based on the optical principle of a slide projector, a visual tristimulus projection colorimeter has been developed. The calorimeter operates with easily interchangeable sets of primary color filters placed in a frame at the objective. The apparatus has proved to be fairly accurate. The reproduction of the color matches as measured by the standard deviation is equal to the visual sensitivity to color differences for each observer. Examples of deviations in the matches among individuals as well as deviations compared with the CIE 1931 Standard Observer are given. These deviations are demonstrated to be solely due to individual differences in the perception of metameric colors. Thus, taking advantage of an objective observation (allowing all adjustments to be judged by a group of impartial observers), the colorimeter provides an excellent aid in the study of discrimination, metamerism, and related effects which are of considerable interest in current research in colorimetry and in the study of color vision tests.

Modelling personality, plasticity and predictability in shelter dogs

PubMed Central

2017-01-01

Behavioural assessments of shelter dogs (Canis lupus familiaris) typically comprise standardized test batteries conducted at one time point, but test batteries have shown inconsistent predictive validity. Longitudinal behavioural assessments offer an alternative. We modelled longitudinal observational data on shelter dog behaviour using the framework of behavioural reaction norms, partitioning variance into personality (i.e. inter-individual differences in behaviour), plasticity (i.e. inter-individual differences in average behaviour) and predictability (i.e. individual differences in residual intra-individual variation). We analysed data on interactions of 3263 dogs (n = 19 281) with unfamiliar people during their first month after arrival at the shelter. Accounting for personality, plasticity (linear and quadratic trends) and predictability improved the predictive accuracy of the analyses compared to models quantifying personality and/or plasticity only. While dogs were, on average, highly sociable with unfamiliar people and sociability increased over days since arrival, group averages were unrepresentative of all dogs and predictions made at the individual level entailed considerable uncertainty. Effects of demographic variables (e.g. age) on personality, plasticity and predictability were observed. Behavioural repeatability was higher one week after arrival compared to arrival day. Our results highlight the value of longitudinal assessments on shelter dogs and identify measures that could improve the predictive validity of behavioural assessments in shelters. PMID:28989764

Individualism and the field viewpoint: cultural influences on memory perspective.

PubMed

Martin, Maryanne; Jones, Gregory V

2012-09-01

Two perspectives from which memories can be retrieved have been distinguished: field resembles the view from the first-person vantage point of original experience, whereas observer resembles the view from the third-person vantage point of a spectator. There is evidence that the incidences of the two types of perspective differ between at least two different cultural groups. It is hypothesised here that this is a special case of a more general relation between memory perspective and cultural individualism, such that field and observer perspectives are more prevalent among people from, respectively, relatively individualist and relatively collectivist societies. Memory perspectives adopted by participants from a range of different countries were recorded, and were found to vary in the predicted manner. Regression analysis showed that the potential effects of three other cultural variables - uncertainty avoidance, masculinity and, to a lesser extent, power distance - were eclipsed by the influence of individualism, and the implications are discussed. Copyright © 2012 Elsevier Inc. All rights reserved.

Escher in color space: individual-differences multidimensional scaling of color dissimilarities collected with a gestalt formation task.

PubMed

Bimler, David; Kirkland, John; Pichler, Shaun

2004-02-01

The structure of color perception can be examined by collecting judgments about color dissimilarities. In the procedure used here, stimuli are presented three at a time on a computer monitor and the spontaneous grouping of most-similar stimuli into gestalts provides the dissimilarity comparisons. Analysis with multidimensional scaling allows such judgments to be pooled from a number of observers without obscuring the variations among them. The anomalous perceptions of color-deficient observers produce comparisons that are represented well by a geometric model of compressed individual color spaces, with different forms of deficiency distinguished by different directions of compression. The geometrical model is also capable of accommodating the normal spectrum of variation, so that there is greater variation in compression parameters between tests on normal subjects than in those between repeated tests on individual subjects. The method is sufficiently sensitive and the variations sufficiently large that they are not obscured by the use of a range of monitors, even under somewhat loosely controlled conditions.

Observation of DNA Molecules Using Fluorescence Microscopy and Atomic Force Microscopy

ERIC Educational Resources Information Center

Ito, Takashi

2008-01-01

This article describes experiments for an undergraduate instrumental analysis laboratory that aim to observe individual double-stranded DNA (dsDNA) molecules using fluorescence microscopy and atomic force microscopy (AFM). dsDNA molecules are observed under several different conditions to discuss their chemical and physical properties. In…

Relations between Spatial Distribution, Social Affiliations and Dominance Hierarchy in a Semi-Free Mandrill Population

PubMed Central

Naud, Alexandre; Chailleux, Eloise; Kestens, Yan; Bret, Céline; Desjardins, Dominic; Petit, Odile; Ngoubangoye, Barthélémy; Sueur, Cédric

2016-01-01

Although there exist advantages to group-living in comparison to a solitary lifestyle, costs and gains of group-living may be unequally distributed among group members. Predation risk, vigilance levels and food intake may be unevenly distributed across group spatial geometry and certain within-group spatial positions may be more or less advantageous depending on the spatial distribution of these factors. In species characterized with dominance hierarchy, high-ranking individuals are commonly observed in advantageous spatial position. However, in complex social systems, individuals can develop affiliative relationships that may balance the effect of dominance relationships in individual's spatial distribution. The objective of the present study is to investigate how the group spatial distribution of a semi-free ranging colony of Mandrills relates to its social organization. Using spatial observations in an area surrounding the feeding zone, we tested the three following hypothesis: (1) does dominance hierarchy explain being observed in proximity or far from a food patch? (2) Do affiliative associations also explain being observed in proximity or far from a food patch? (3) Do the differences in rank in the group hierarchy explain being co-observed in proximity of a food patch? Our results showed that high-ranking individuals were more observed in proximity of the feeding zone while low-ranking individuals were more observed at the boundaries of the observation area. Furthermore, we observed that affiliative relationships were also associated with individual spatial distributions and explain more of the total variance of the spatial distribution in comparison with dominance hierarchy. Finally, we found that individuals observed at a same moment in proximity of the feeding zone were more likely to be distant in the hierarchy while controlling for maternal kinship, age and sex similarity. This study brings some elements about how affiliative networks and dominance hierarchy are related to spatial positions in primates. PMID:27199845

Relations between Spatial Distribution, Social Affiliations and Dominance Hierarchy in a Semi-Free Mandrill Population.

PubMed

Naud, Alexandre; Chailleux, Eloise; Kestens, Yan; Bret, Céline; Desjardins, Dominic; Petit, Odile; Ngoubangoye, Barthélémy; Sueur, Cédric

2016-01-01

Although there exist advantages to group-living in comparison to a solitary lifestyle, costs and gains of group-living may be unequally distributed among group members. Predation risk, vigilance levels and food intake may be unevenly distributed across group spatial geometry and certain within-group spatial positions may be more or less advantageous depending on the spatial distribution of these factors. In species characterized with dominance hierarchy, high-ranking individuals are commonly observed in advantageous spatial position. However, in complex social systems, individuals can develop affiliative relationships that may balance the effect of dominance relationships in individual's spatial distribution. The objective of the present study is to investigate how the group spatial distribution of a semi-free ranging colony of Mandrills relates to its social organization. Using spatial observations in an area surrounding the feeding zone, we tested the three following hypothesis: (1) does dominance hierarchy explain being observed in proximity or far from a food patch? (2) Do affiliative associations also explain being observed in proximity or far from a food patch? (3) Do the differences in rank in the group hierarchy explain being co-observed in proximity of a food patch? Our results showed that high-ranking individuals were more observed in proximity of the feeding zone while low-ranking individuals were more observed at the boundaries of the observation area. Furthermore, we observed that affiliative relationships were also associated with individual spatial distributions and explain more of the total variance of the spatial distribution in comparison with dominance hierarchy. Finally, we found that individuals observed at a same moment in proximity of the feeding zone were more likely to be distant in the hierarchy while controlling for maternal kinship, age and sex similarity. This study brings some elements about how affiliative networks and dominance hierarchy are related to spatial positions in primates.

Breaking the Myth That Relay Swimming Is Faster Than Individual Swimming.

PubMed

Skorski, Sabrina; Etxebarria, Naroa; Thompson, Kevin G

2016-04-01

To investigate if swimming performance is better in a relay race than in the corresponding individual race. The authors analyzed 166 elite male swimmers from 15 nations in the same competition (downloaded from www.swimrankings.net). Of 778 observed races, 144 were Olympic Games performances (2000, 2004, 2012), with the remaining 634 performed in national or international competitions. The races were 100-m (n = 436) and 200-m (n = 342) freestyle events. Relay performance times for the 2nd-4th swimmers were adjusted (+ 0.73 s) to allow for the "flying start." Without any adjustment, mean individual relay performances were significantly faster for the first 50 m and overall time in the 100-m events. Furthermore, the first 100 m of the 200-m relay was significantly faster (P > .001). During relays, swimmers competing in 1st position did not show any difference compared with their corresponding individual performance (P > .16). However, swimmers competing in 2nd-4th relay-team positions demonstrated significantly faster times in the 100-m (P < .001) and first half of the 200-m relays than in their individual events (P < .001, ES: 0.28-1.77). However, when finishing times for 2nd-4th relay team positions were adjusted for the flying start no differences were detected between relay and individual race performance for any event or split time (P > .17). Highly trained swimmers do not swim (or turn) faster in relay events than in their individual races. Relay exchange times account for the difference observed in individual vs relay performance.

Determination of low-Z elements in individual environmental particles using windowless EPMA.

PubMed

Ro, C U; Osán, J; Van Grieken, R

1999-04-15

The determination of low-Z elements such as carbon, nitrogen, and oxygen in atmospheric aerosol particles is of interest in studying environmental pollution. Conventional electron probe microanalysis technique has a limitation for the determination of the low-Z elements, mainly because the Be window in an energy-dispersive X-ray (EDX) detector hinders the detection of characteristic X-rays from light elements. The feasibility of low-Z element determination in individual particles using a windowless EDX detector is investigated. To develop a method capable of identifying chemical species of individual particles, both the matrix and the geometric effects of particles have to be evaluated. X-rays of low-Z elements generated by an electron beam are so soft that important matrix effects, mostly due to X-ray absorption, exist even within particles in the micrometer size range. Also, the observed radiation, especially that of light elements, experiences different extents of absorption, depending on the shape and size of the particles. Monte Carlo calculation is applied to explain the variation of observed X-ray intensities according to the geometric and chemical compositional variation of individual particles, at different primary electron beam energies. A comparison is carried out between simulated and experimental data, collected for standard individual particles with chemical compositions as generally observed in marine and continental aerosols. Despite the many fundamental problematic analytical factors involved in the observation of X-rays from low-Z elements, the Monte Carlo calculation proves to be quite reliable to evaluate those matrix and geometric effects. Practical aspects of the Monte Carlo calculation for the determination of light elements in individual particles are also considered.

Evidence of Sr/Ca and Mg/Ca Temperature Invariance in Live Aragonitic Hoeglundina elegans Tests from the Little Bahama Bank

NASA Astrophysics Data System (ADS)

Blanks, J. K.; Hintz, C. J.; Chandler, G. T.; Shaw, T. J.; McCorkle, D. C.; Bernhard, J. M.

2007-12-01

Mg/Ca and Sr/Ca were analyzed from core-top individual Hoeglundina elegans aragonitic tests collected from three continental slope depths within the South Carolina and Little Bahama Bank continental slope environs (220 m to 1084 m). Our study utilized only individuals that labeled with the vital probe CellTracker Green - unlike bulk core-top material often stained with Rose Bengal, which has known inconsistencies in distinguishing live from dead foraminifera. DSr x 10 values were consistently 1.74 $ pm 0.23 across all sampling depths. The analytical error in DSr values (0.7%) determined by ICP-MS between repeated measurements on individual H. elegans tests across all depths was less than analytical error on repeated measurements from standards. Variation in DSr values was not directly explained by a linear temperature relationship (p=0.0003, R2=0.44) over the temperature range of 4.9-11.4°C with a sensitivity of 59.8 μmol/mol/1°C. The standard error by regressing DSr across temperature yields + 3.4°C, which is nearly 3x greater that reported in previous studies. Sr/Ca was more sensitive for calibrating temperature than Mg/Ca in H. elegans. Observed scatter in DSr was too great across individuals of the same size and of different sizes to resolve ontogenetic effects. However, higher DSr values were associated with smaller individuals and warmer/shallower sampling depths. The highest DSr values were observed at the intermediate sampling depth (~600 m). No significant ontogenetic relationship was found across DSr values in different sized individuals due to tighter overall constrained variance; however lower DSr values were observed from several smaller individuals. Several dead tests of H. elegans showed no significant differences in DSr values compared to live specimens cleaned by standard cleaning methods, unlike higher dead than live DMg values observed for the same individuals. There were no significant deviations in DSr across batches cleaned on separate days, unlike the observed sensitivity of DMg across batches. A subset of samples were reductively cleaned (hydrazine solution); and exhibited DMg values within analytical precision of those observed for non-reductively cleaned samples. Therefore, deviations in DMg values resulting from the removal of the reductive cleaning step did not explain analytical errors greater than published values for Mg/Ca or the high variance across same sized individuals. Variation in DMg values across the same cleaning methods and from dead individuals suggests the need for a careful look into how foraminiferal aragonite should be processed. These findings provide evidence that both Mg and Sr in benthic foraminiferal aragonite reflect factors in addition to temperature and pressure that may interfere with absolute temperature calibrations. Funded by NSF OCE 0351029, OCE 0437366, and OCE-0350794.

Testing the predictions of coping styles theory in threespined sticklebacks

PubMed Central

Bensky, Miles K.; Paitz, Ryan; Pereira, Laura; Bell, Alison M.

2017-01-01

Coping styles theory provides a framework for understanding individual variation in how animals respond to environmental change, and predicts how individual differences in stress responsiveness and behavior might relate to cognitive differences. According to coping styles theory, proactive individuals are bolder, less reactive to stressors, and more routinized than their reactive counterparts. A key tenet of coping styles theory is that variation in coping styles is maintained by tradeoffs with behavioral flexibility: proactive individuals excel in stable environments while more flexible, reactive individuals perform better in variable environments. Here, we assess evidence for coping styles within a natural population of threespined sticklebacks (Gasterosteus aculeatus). We developed a criterion-based learning paradigm to evaluate individual variation in initial and reversal learning. We observed strong individual differences in boldness, cortisol production, and learning performance. Consistent with coping styles, fish that released more cortisol were more timid in response to a predator attack and slower to learn a color discrimination task. However, there was no evidence that reactive individuals performed better when the environment changed (when the rewarded color was reversed). The failure to detect trade-offs between behavioral routinization and flexibility prompts other explanations for the maintenance of differing coping styles. PMID:28017848

Validation of individual and aggregate global flood hazard models for two major floods in Africa.

NASA Astrophysics Data System (ADS)

Trigg, M.; Bernhofen, M.; Whyman, C.

2017-12-01

A recent intercomparison of global flood hazard models undertaken by the Global Flood Partnership shows that there is an urgent requirement to undertake more validation of the models against flood observations. As part of the intercomparison, the aggregated model dataset resulting from the project was provided as open access data. We compare the individual and aggregated flood extent output from the six global models and test these against two major floods in the African Continent within the last decade, namely severe flooding on the Niger River in Nigeria in 2012, and on the Zambezi River in Mozambique in 2007. We test if aggregating different number and combination of models increases model fit to the observations compared with the individual model outputs. We present results that illustrate some of the challenges of comparing imperfect models with imperfect observations and also that of defining the probability of a real event in order to test standard model output probabilities. Finally, we propose a collective set of open access validation flood events, with associated observational data and descriptions that provide a standard set of tests across different climates and hydraulic conditions.

Force-velocity property of leg muscles in individuals of different level of physical fitness

PubMed Central

Cuk, Ivan; Mirkov, Dragan; Nedeljkovic, Aleksandar; Kukolj, Milos; Ugarkovic, Dusan; Jaric, Slobodan

2016-01-01

The present study explored the method of testing muscle mechanical properties through the linear force-velocity (F–V) relationships obtained from loaded vertical jumps. Specifically, we hypothesised that the F-V relationship parameters depicting the force, power, and velocity of the tested muscles will differ among individuals of different physical fitness. Strength trained, physically active, and sedentary male participants (N=10+10+10; age 20–29 years) were tested on maximum countermovement and squat jumps where manipulation of external loads provided a range of F and V data. The observed F–V relationships of the tested leg muscles were approximately linear and mainly strong (median correlation coefficients ranged from 0.77 to 0.92; all p < 0.05), independently of either the tested group or the jump type. The maximum power revealed higher values in the strength trained than in the physically active and sedentary participants. This difference originated from the differences in F-intercepts, rather than from the V-intercepts. We conclude that the observed parameters could be sensitive enough to detect the differences among both the individuals of different physical fitness and various jump types. The present findings support using loaded vertical jumps and, possibly, other maximum performance multi-joint movements for the assessment of mechanical properties of active muscles. PMID:27111493

Repeatable and heritable behavioural variation in a wild cooperative breeder

PubMed Central

Burke, Terry; Dugdale, Hannah L.

2017-01-01

Abstract Quantifying consistent differences in behaviour among individuals is vital to understanding the ecological and evolutionary significance of animal personality. To quantify personality, the phenotypic variation of a behavioural trait is partitioned to assess how it varies among individuals, which is also known as repeatability. If pedigree data are available, the phenotypic variation can then be further partitioned to estimate the additive genetic variance and heritability. Assessing the repeatability and heritability of personality traits therefore allows for a better understanding of what natural selection can act upon, enabling evolution. In a natural population of facultative cooperatively breeding Seychelles warbler (Acrocephalus sechellensis) on Cousin Island, a lack of breeding vacancies forces individuals into different life-history strategies, and these differences in reproductive state could generate behavioural differences among individuals in the population. We used this population to estimate the repeatability of 4 behavioural traits (novel environment exploration, novel object exploration, obstinacy/struggle rate, and escape response), and narrow-sense heritability (of behavior, h2B; behavior minus observer variance; and personality), and evolvability, of the repeatable behavioural traits. We also tested for an among-individual correlation between the repeatable traits. We found that, compared to estimates in other study species, the exploratory behaviours were moderately repeatable (0.23–0.37), there was a positive among-individual correlation (0.51) between novel environment and novel object exploration, and that novel environment exploration was moderately heritable (0.17; h2B was low as it includes observer variance). This study further clarifies the additive genetic variance available for selection to act upon in this cooperatively breeding bird. PMID:29622921

Individual Differences in Language Acquisition and Processing.

PubMed

Kidd, Evan; Donnelly, Seamus; Christiansen, Morten H

2018-02-01

Humans differ in innumerable ways, with considerable variation observable at every level of description, from the molecular to the social. Traditionally, linguistic and psycholinguistic theory has downplayed the possibility of meaningful differences in language across individuals. However, it is becoming increasingly evident that there is significant variation among speakers at any age as well as across the lifespan. Here, we review recent research in psycholinguistics, and argue that a focus on individual differences (IDs) provides a crucial source of evidence that bears strongly upon core issues in theories of the acquisition and processing of language; specifically, the role of experience in language acquisition, processing, and attainment, and the architecture of the language system. Copyright © 2017 Elsevier Ltd. All rights reserved.

Negative Affect, Decision Making, and Attentional Networks.

PubMed

Ortega, Ana Raquel; Ramírez, Encarnación; Colmenero, José María; García-Viedma, Ma Del Rosario

2017-02-01

This study focuses on whether risk avoidance in decision making depends on negative affect or it is specific to anxious individuals. The Balloon Analogue Risk Task was used to obtain an objective measure in a risk situation with anxious, depressive, and control individuals. The role of attentional networks was also studied using the Attentional Network Test-Interaction (ANT-I) task with neutral stimuli. A significant difference was observed between anxious and depressive individuals in assumed risk in decision making. We found no differences between anxious and normal individuals in the alert, orientation, and congruency effects obtained in the ANT-I task. The results showed that there was no significant relationship between the risk avoidance and the indexes of alertness, orienting, and control. Future research shall determine whether emotionally relevant stimulation leads to attentional control deficit or whether differences between anxious and no anxious individuals are due to the type of strategy followed in choice tasks.

Novel Perceptually Uniform Chromatic Space.

PubMed

da Fonseca, María; Samengo, Inés

2018-06-01

Chromatically perceptive observers are endowed with a sense of similarity between colors. For example, two shades of green that are only slightly discriminable are perceived as similar, whereas other pairs of colors, for example, blue and yellow, typically elicit markedly different sensations. The notion of similarity need not be shared by different observers. Dichromat and trichromat subjects perceive colors differently, and two dichromats (or two trichromats, for that matter) may judge chromatic differences inconsistently. Moreover, there is ample evidence that different animal species sense colors diversely. To capture the subjective metric of color perception, here we construct a notion of distance in color space based on the physiology of the retina, and is thereby individually tailored for different observers. By applying the Fisher metric to an analytical model of color representation, we construct a notion of distance that reproduces behavioral experiments of classical discrimination tasks. We then derive a coordinate transformation that defines a new chromatic space in which the Euclidean distance between any two colors is equal to the perceptual distance, as seen by one individual subject, endowed with an arbitrary number of color-sensitive photoreceptors, each with arbitrary absorption probability curves and appearing in arbitrary proportions.

Preferred computer activities among individuals with dementia: a pilot study.

PubMed

Tak, Sunghee H; Zhang, Hongmei; Hong, Song Hee

2015-03-01

Computers offer new activities that are easily accessible, cognitively stimulating, and enjoyable for individuals with dementia. The current descriptive study examined preferred computer activities among nursing home residents with different severity levels of dementia. A secondary data analysis was conducted using activity observation logs from 15 study participants with dementia (severe = 115 logs, moderate = 234 logs, and mild = 124 logs) who participated in a computer activity program. Significant differences existed in preferred computer activities among groups with different severity levels of dementia. Participants with severe dementia spent significantly more time watching slide shows with music than those with both mild and moderate dementia (F [2,12] = 9.72, p = 0.003). Preference in playing games also differed significantly across the three groups. It is critical to consider individuals' interests and functional abilities when computer activities are provided for individuals with dementia. A practice guideline for tailoring computer activities is detailed. Copyright 2015, SLACK Incorporated.

Spontaneous individual differences in cognitive performances of young adult rats predict locomotor response to amphetamine.

PubMed

Dellu-Hagedorn, F

2005-01-01

Inter-individual differences in cognitive capacities of young adult rats have largely been ignored. To explore this variability and its neurobiological bases, the relationships between individual differences in working memory and locomotor responses to novelty and to amphetamine were investigated in SD rats. Groups of good and poor learners were isolated, the latter demonstrating a markedly slower learning of the task compared to performant rats, with more perseverations independently to motivational state. They also presented a much higher increase in amphetamine-induced locomotion that remained significant for more than 1h after the injection. These results provide evidence that variability in cognitive capacities can be used to reveal their neurobiological substrates. They open new perspectives to study a possible cognitive origin of addictive behaviors and to investigate the involvement of these inter-individual differences on those observed later in life.

Quantifying space use of breeders and floaters of a long-lived species using individual movement data.

PubMed

Penteriani, Vincenzo; del Mar Delgado, Maria; Campioni, Letizia

2015-06-01

To date, animal movement studies have mostly analysed the movement behaviours of individuals at specific times of their lives, but we lack detailed information on how individual movements may be affected by the various and different changes that individuals experience throughout their life (e.g. life history phases, experience, age). Here, we attempt to identify differences in home range and movement behaviour between two different statuses, disperser vs. breeder, of a long-lived species (the eagle owl Bubo bubo). Information on home range and movement behaviour between different stages of an individual life are crucial for species conservation and management, as well as for basic knowledge on space use and rhythm of activity. Does the transition from an exploratory stage to moving within more familiar surroundings call for changes in the movement behaviour? We observed notable differences during the two stages of the owls' lives, with individuals having different home range behaviours and rhythms of activity depending on their social status. Significant differences in home range behaviour between the sexes began only with the acquisition of a breeding site. Breeders showed larger home ranges than dispersing individuals, although nightly variation of home ranges size was higher for dispersers than for breeders. Finally, dispersers were active throughout the night, whereas breeders displayed a less active movement phase at both the beginning and end of the night. Our results demonstrate it is important to consider individual variations in space use and movement behaviour due to the different life history phases that they attain during their lifetime. The knowledge of the different needs of a species across life stages may represent an important tool for species conservation because each phase of an individual life may need different requirements.

Quantifying space use of breeders and floaters of a long-lived species using individual movement data

NASA Astrophysics Data System (ADS)

Penteriani, Vincenzo; del Mar Delgado, Maria; Campioni, Letizia

2015-06-01

To date, animal movement studies have mostly analysed the movement behaviours of individuals at specific times of their lives, but we lack detailed information on how individual movements may be affected by the various and different changes that individuals experience throughout their life (e.g. life history phases, experience, age). Here, we attempt to identify differences in home range and movement behaviour between two different statuses, disperser vs. breeder, of a long-lived species (the eagle owl Bubo bubo). Information on home range and movement behaviour between different stages of an individual life are crucial for species conservation and management, as well as for basic knowledge on space use and rhythm of activity. Does the transition from an exploratory stage to moving within more familiar surroundings call for changes in the movement behaviour? We observed notable differences during the two stages of the owls' lives, with individuals having different home range behaviours and rhythms of activity depending on their social status. Significant differences in home range behaviour between the sexes began only with the acquisition of a breeding site. Breeders showed larger home ranges than dispersing individuals, although nightly variation of home ranges size was higher for dispersers than for breeders. Finally, dispersers were active throughout the night, whereas breeders displayed a less active movement phase at both the beginning and end of the night. Our results demonstrate it is important to consider individual variations in space use and movement behaviour due to the different life history phases that they attain during their lifetime. The knowledge of the different needs of a species across life stages may represent an important tool for species conservation because each phase of an individual life may need different requirements.

Correlates of individual differences in compensatory nicotine self-administration in rats following a decrease in nicotine unit dose

PubMed Central

Harris, Andrew C.; Pentel, Paul R.; LeSage, Mark G.

2013-01-01

Rationale The ability of tobacco harm reduction strategies to produce significant reductions in toxin exposure is limited by compensatory increases in smoking behavior. Characterizing factors contributing to the marked individual variability in compensation may be useful for understanding this phenomenon and assessing the feasibility of harm reduction interventions. Objective To use an animal model of human compensatory smoking that involves a decrease in unit dose supporting nicotine self-administration (NSA) to examine potential contributors to individual differences in compensation. Methods Rats were trained for NSA during daily 23 hr sessions at a unit dose of 0.06 mg/kg/inf until responding was stable. The unit dose was then reduced to 0.03 mg/kg/inf for at least 10 sessions. Following reacquisition of NSA at the training dose and extinction, single-dose nicotine pharmacokinetic parameters were determined. Results Decreases in nicotine intake following dose reduction were proportionally less than the decrease in unit dose, indicating partial compensation. Compensatory increases in infusion rates were observed across the course of the 23 hr sessions. The magnitude of compensation differed considerably between rats. Rats exhibiting the highest baseline infusion rates exhibited the lowest levels of compensation. Nicotine pharmacokinetic parameters were not significantly correlated with compensation. Infusion rates immediately returned to pre-reduction levels when baseline conditions were restored. Conclusions These findings provide initial insights into correlates of individual differences in compensation following a reduction in nicotine unit dose. The present assay may be useful for characterizing mechanisms and potential consequences of the marked individual differences in compensatory smoking observed in humans. PMID:19475400

The Influence of Personality on Neural Mechanisms of Observational Fear and Reward Learning

ERIC Educational Resources Information Center

Hooker, Christine I.; Verosky, Sara C.; Miyakawa, Asako; Knight, Robert T.; D'Esposito, Mark

2008-01-01

Fear and reward learning can occur through direct experience or observation. Both channels can enhance survival or create maladaptive behavior. We used fMRI to isolate neural mechanisms of observational fear and reward learning and investigate whether neural response varied according to individual differences in neuroticism and extraversion.…

Within- and between-year dispersal of American Avocets among multiple western Great Basin wetlands

USGS Publications Warehouse

Plissner, Jonathan H.; Haig, Susan M.; Oring, L.W.

1999-01-01

Connectivity of discrete habitat patches may be described in terms of the movements of individual organisms among such patches. To examine connectivity of widely dispersed alkali lake systems, we recorded post-breeding and subsequent breeding locations of color-banded American Avocets (Recurvirostra americana) in the western U.S. Great Basin, from 1995-1997. Among individuals observed during the post-breeding/premigratory season, over half of the 188 breeding adults were observed at lakes other than their breeding locations, whereas 70% of 125 post-fledged young were observed only at their natal lake systems. Of 46 breeding adults observed in consecutive years, only eight (17%) dispersed between different lake systems. Only 8% of chicks were observed after their first year, and only 1.3% returned to the natal area in subsequent breeding seasons. Adult and recently fledged birds from the southernmost breeding site were regularly observed in post-breeding aggregations at lakes several hundred kilometers to the north, suggesting seasonal differences in habitat quality at the lake systems studied. These results indicate the importance of maintaining habitat for post-breeding movements.

Effect of individual shades on reliability and validity of observers in colour matching.

PubMed

Lagouvardos, P E; Diamanti, H; Polyzois, G

2004-06-01

The effect of individual shades in shade guides, on the reliability and validity of measurements in a colour matching process is very important. Observer's agreement on shades and sensitivity/specificity of shades, can give us an estimate of shade's effect on observer's reliability and validity. In the present study, a group of 16 students, matched 15 shades of a Kulzer's guide and 10 human incisors to Kulzer's and/or Vita's shade tabs, in 4 different tests. The results showed shades I, B10, C40, A35 and A10 were those with the highest reliability and validity values. In conclusion, a) the matching process with shades of different materials was not accurate enough, b) some shades produce a more reliable and valid match than others and c) teeth are matched with relative difficulty.

Individual differences in heart rate variability are associated with the avoidance of negative emotional events.

PubMed

Katahira, Kentaro; Fujimura, Tomomi; Matsuda, Yoshi-Taka; Okanoya, Kazuo; Okada, Masato

2014-12-01

Although the emotional outcome of a choice generally affects subsequent decisions, humans can inhibit the influence of emotion. Heart rate variability (HRV) has emerged as an objective measure of individual differences in the capacity for inhibitory control. In the present study, we investigated how individual differences in HRV at rest are associated with the emotional effects of the outcome of a choice on subsequent decision making using a decision-making task in which emotional pictures appeared as decision outcomes. We used a reinforcement learning model to characterize the observed behaviors according to several parameters, namely, the learning rate and the motivational value of positive and negative pictures. Consequently, we found that individuals with a lower resting HRV exhibited a greater negative motivational value in response to negative pictures, suggesting that these individuals tend to avoid negative pictures compared with individuals with a higher resting HRV. Copyright © 2014 Elsevier B.V. All rights reserved.

Infrared sensing of non-observable human biometrics

NASA Astrophysics Data System (ADS)

Willmore, Michael R.

2005-05-01

Interest and growth of biometric recognition technologies surged after 9/11. Once a technology mainly used for identity verification in law enforcement, biometrics are now being considered as a secure means of providing identity assurance in security related applications. Biometric recognition in law enforcement must, by necessity, use attributes of human uniqueness that are both observable and vulnerable to compromise. Privacy and protection of an individual's identity is not assured during criminal activity. However, a security system must rely on identity assurance for access control to physical or logical spaces while not being vulnerable to compromise and protecting the privacy of an individual. The solution resides in the use of non-observable attributes of human uniqueness to perform the biometric recognition process. This discussion will begin by presenting some key perspectives about biometric recognition and the characteristic differences between observable and non-observable biometric attributes. An introduction to the design, development, and testing of the Thermo-ID system will follow. The Thermo-ID system is an emerging biometric recognition technology that uses non-observable patterns of infrared energy naturally emanating from within the human body. As with all biometric systems, the infrared patterns recorded and compared within the Thermo-ID system are unique and individually distinguishable permitting a link to be confirmed between an individual and a claimed or previously established identity. The non-observable characteristics of infrared patterns of human uniqueness insure both the privacy and protection of an individual using this type of biometric recognition system.

Human Body Odour Composites Are Not Perceived More Positively than the Individual Samples.

PubMed

Fialová, Jitka; Sorokowska, Agnieszka; Roberts, S Craig; Kubicová, Lydie; Havlíček, Jan

2018-01-01

It is well established that composite facial images are perceived as more attractive compared with individual images, suggesting a preference for heterozygosity. Similarly, there is evidence that preferences for body odours might be linked to heterozygosity. Here, we tested whether blending individual body odours into composites would follow a similar pattern as observed in the perception of faces. We collected axillary odour samples from 38 individuals, which were subsequently assessed individually and as composites of two ( N  = 19) or four ( N  = 9) body odours regarding their pleasantness, attractiveness and intensity. We found no significant differences between mean ratings of individual odour samples or composites of two or four odour samples. Our results indicate that, in contrast to faces, composite body odours are not rated as more attractive. Composite body odours retain similar hedonic perceptual qualities as individual odours, thus highlighting differences in visual and chemosensory perceptual mechanisms.

Human Body Odour Composites Are Not Perceived More Positively than the Individual Samples

PubMed Central

Fialová, Jitka; Sorokowska, Agnieszka; Roberts, S. Craig; Kubicová, Lydie; Havlíček, Jan

2018-01-01

It is well established that composite facial images are perceived as more attractive compared with individual images, suggesting a preference for heterozygosity. Similarly, there is evidence that preferences for body odours might be linked to heterozygosity. Here, we tested whether blending individual body odours into composites would follow a similar pattern as observed in the perception of faces. We collected axillary odour samples from 38 individuals, which were subsequently assessed individually and as composites of two (N = 19) or four (N = 9) body odours regarding their pleasantness, attractiveness and intensity. We found no significant differences between mean ratings of individual odour samples or composites of two or four odour samples. Our results indicate that, in contrast to faces, composite body odours are not rated as more attractive. Composite body odours retain similar hedonic perceptual qualities as individual odours, thus highlighting differences in visual and chemosensory perceptual mechanisms. PMID:29770184

Sex differences in the influence of body mass index on anatomical architecture of brain networks.

PubMed

Gupta, A; Mayer, E A; Hamadani, K; Bhatt, R; Fling, C; Alaverdyan, M; Torgerson, C; Ashe-McNalley, C; Van Horn, J D; Naliboff, B; Tillisch, K; Sanmiguel, C P; Labus, J S

2017-08-01

The brain has a central role in regulating ingestive behavior in obesity. Analogous to addiction behaviors, an imbalance in the processing of rewarding and salient stimuli results in maladaptive eating behaviors that override homeostatic needs. We performed network analysis based on graph theory to examine the association between body mass index (BMI) and network measures of integrity, information flow and global communication (centrality) in reward, salience and sensorimotor regions and to identify sex-related differences in these parameters. Structural and diffusion tensor imaging were obtained in a sample of 124 individuals (61 males and 63 females). Graph theory was applied to calculate anatomical network properties (centrality) for regions of the reward, salience and sensorimotor networks. General linear models with linear contrasts were performed to test for BMI and sex-related differences in measures of centrality, while controlling for age. In both males and females, individuals with high BMI (obese and overweight) had greater anatomical centrality (greater connectivity) of reward (putamen) and salience (anterior insula) network regions. Sex differences were observed both in individuals with normal and elevated BMI. In individuals with high BMI, females compared to males showed greater centrality in reward (amygdala, hippocampus and nucleus accumbens) and salience (anterior mid-cingulate cortex) regions, while males compared to females had greater centrality in reward (putamen) and sensorimotor (posterior insula) regions. In individuals with increased BMI, reward, salience and sensorimotor network regions are susceptible to topological restructuring in a sex-related manner. These findings highlight the influence of these regions on integrative processing of food-related stimuli and increased ingestive behavior in obesity, or in the influence of hedonic ingestion on brain topological restructuring. The observed sex differences emphasize the importance of considering sex differences in obesity pathophysiology.

Sex Differences in the Influence of Body Mass Index on Anatomical Architecture of Brain Networks

PubMed Central

Gupta, Arpana; Mayer, Emeran A.; Hamadani, Kareem; Bhatt, Ravi; Fling, Connor; Alaverdyan, Mher; Torgenson, Carinna; Ashe-McNalley, Cody; Van Horn, John D; Naliboff, Bruce; Tillisch, Kirsten; Sanmiguel, Claudia P.; Labus, Jennifer S.

2017-01-01

Background/Objective The brain plays a central role in regulating ingestive behavior in obesity. Analogous to addiction behaviors, an imbalance in the processing of rewarding and salient stimuli results in maladaptive eating behaviors that override homeostatic needs. We performed network analysis based on graph theory to examine the association between body mass index (BMI) and network measures of integrity, information flow, and global communication (centrality) in reward, salience and sensorimotor regions, and to identify sex-related differences in these parameters. Subjects/Methods Structural and diffusion tensor imaging were obtained in a sample of 124 individuals (61 males and 63 females). Graph theory was applied to calculate anatomical network properties (centrality) for regions of the reward, salience, and sensorimotor networks. General linear models with linear contrasts were performed to test for BMI and sex-related differences in measures of centrality, while controlling for age. Results In both males and females, individuals with high BMI (obese and overweight) had greater anatomical centrality (greater connectivity) of reward (putamen) and salience (anterior insula) network regions. Sex differences were observed both in individuals with normal and elevated BMI. In individuals with high BMI, females compared to males showed greater centrality in reward (amygdala, hippocampus, nucleus accumbens) and salience (anterior mid cingulate cortex) regions, while males compared to females had greater centrality in reward (putamen) and sensorimotor (posterior insula) regions. Conclusions In individuals with increased BMI, reward, salience, and sensorimotor network regions are susceptible to topological restructuring in a sex related manner. These findings highlight the influence of these regions on integrative processing of food-related stimuli and increased ingestive behavior in obesity, or in the influence of hedonic ingestion on brain topological restructuring. The observed sex differences emphasize the importance of considering sex differences in obesity pathophysiology. PMID:28360430

GENDER BASED DIFFERENCES IN ENDOCRINE AND REPRODUCTIVE TOXICITY

EPA Science Inventory

Basic differences in male versus female reproductive physiology lead to differentials in their respective susceptibilities to chemical insult as evidenced by a variety of observations. As individuals undergo maturation from prenatal sex differentiation through pubertal developme...

Optimization of Maillard Reaction between Glucosamine and Other Precursors by Measuring Browning with a Spectrophotometer.

PubMed

Ogutu, Benrick; Kim, Ye-Joo; Kim, Dae-Wook; Oh, Sang-Chul; Hong, Dong-Lee; Lee, Yang-Bong

2017-09-01

The individual Maillard reactions of glucose, glucosamine, cyclohexylamine, and benzylamine were studied at a fixed temperature of 120°C under different durations by monitoring the absorbance of the final products at 425 nm. Glucosamine was the most individually reactive compound, whereas the reactions of glucose, cyclohexylamine, and benzylamine were not significantly different from each other. Maillard reactions of reaction mixtures consisting of glucosamine-cyclohexylamine, glucosamine-benzylamine, glucose-cyclohexylamine, and glucose-benzylamine were also studied using different concentration ratios under different durations at a fixed temperature of 120°C and pH 9. Maillard reactions in the pairs involving glucosamine were observed to be more intense than those of the pairs involving glucose. Finally, with respect to the concentration ratios, it was observed that in most instances, optimal activity was realized, when the reaction mixtures were in the ratio of 1:1.

Optimization of Maillard Reaction between Glucosamine and Other Precursors by Measuring Browning with a Spectrophotometer

PubMed Central

Ogutu, Benrick; Kim, Ye-Joo; Kim, Dae-Wook; Oh, Sang-Chul; Hong, Dong-Lee; Lee, Yang-Bong

2017-01-01

The individual Maillard reactions of glucose, glucosamine, cyclohexylamine, and benzylamine were studied at a fixed temperature of 120°C under different durations by monitoring the absorbance of the final products at 425 nm. Glucosamine was the most individually reactive compound, whereas the reactions of glucose, cyclohexylamine, and benzylamine were not significantly different from each other. Maillard reactions of reaction mixtures consisting of glucosamine-cyclohexylamine, glucosamine-benzylamine, glucose-cyclohexylamine, and glucose-benzylamine were also studied using different concentration ratios under different durations at a fixed temperature of 120°C and pH 9. Maillard reactions in the pairs involving glucosamine were observed to be more intense than those of the pairs involving glucose. Finally, with respect to the concentration ratios, it was observed that in most instances, optimal activity was realized, when the reaction mixtures were in the ratio of 1:1. PMID:29043219

Children's self-allocation and use of classroom curricular time.

PubMed

Ingram, J; Worrall, N

1992-02-01

A class of 9-10 year-olds (N = 12) in a British primary school were observed as it moved over a one-year period through three types of classroom environment, traditional directive, transitional negotiative and established negotiative. Each environment offered the children a differing relationship with curricular time, its control and allocation, moving from teacher-allocated time to child allocation. Pupil self-report and classroom observation indicated differences in the balance of curricular spread and allocated time on curricular subject in relation to the type of classroom organisation and who controlled classroom time. These differences were at both class and individual child level. The established negotiative environment recorded the most equitable curricular balance, traditional directive the least. While individual children responded differently within and across the three classroom environments, the established negotiative where time was under child control recorded preference for longer activity periods compared to where the teacher controlled time allocations.

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

Minchin, Robert F., E-mail: rminchin@naic.edu

I investigate whether it is possible to reconcile the recent Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) observation that the neutral hydrogen mass function (HIMF) across different galactic densities has the same, non-flat, faint-end slope, with observations of isolated galaxies and many galaxy groups that show their HIMFs to have flat faint-end slopes. I find that a fairly simple model in which the position of the knee in the mass function of each individual group is allowed to vary is able to account for both of these observations. If this model reflects reality, the ALFALFA results point to anmore » interesting “conspiracy” whereby the differing group HIMFs always sum up to form global HIMFs with the same faint-end slope in different environments. More generally, this result implies that global environmental HIMFs do not necessarily reflect the HIMFs in individual groups belonging to that environment and cannot be used to directly measure variations in group-specific HIMFs with environment.« less

How training citizen scientists affects the accuracy and precision of phenological data.

PubMed

Feldman, Richard E; Žemaitė, Irma; Miller-Rushing, Abraham J

2018-05-07

Monitoring plant and animal phenology is a critical step to anticipating and predicting changes in species interactions and biodiversity. Because phenology necessarily involves frequent and repeated observations over time, citizen scientists have become a vital part of collecting phenological data. However, there is still concern over the accuracy and precision of citizen science data. It is possible that training citizen scientists can improve data quality though there are few comparisons of trained and untrained citizen scientists in the ability of each to accurately and precisely measure phenology. We assessed how three types of observers-experts, trained citizen scientists that make repeated observations, and untrained citizen scientists making once-per-year observations-differ in quantifying temporal change in flower and fruit abundance of American mountain ash trees (Sorbus americana Marsh.) and arthropods in Acadia National Park, Maine, USA. We found that trained more so than untrained citizen science observers over- or under-estimated abundances leading to precise but inaccurate characterizations of phenological patterns. Our results suggest a new type of bias induced by repeated observations: A type of learning takes place that reduces the independence of observations taken on different trees or different dates. Thus, in this and many other cases, having individuals make one-off observations of marked plants may produce data as good if not better than individuals making repeated observations. For citizen science programs related to phenology, our results underscore the importance of (a) attracting the most number of observers possible even if they only make one observation, (b) producing easy-to-use and informative data sheets, and (c) carefully planning effective training programs that are, perhaps, repeated at different points during the data collection period.

The effect of a physiotherapy education compared with a non-healthcare education on the attitudes and beliefs of students towards functioning in individuals with back pain: an observational, cross-sectional study.

PubMed

Ryan, Cormac; Murphy, Dervla; Clark, Michael; Lee, Andrew

2010-06-01

To investigate the difference in attitudes: (1) between first and fourth year physiotherapy students towards functioning in individuals with back pain; and (2) between physiotherapy students and non-healthcare students towards functioning in individuals with back pain. Observational, cross-sectional study. Glasgow Caledonian University, Scotland, UK. First year physiotherapy (n=61) and non-healthcare students (n=61), and fourth year physiotherapy (n=62) and non-healthcare students (n=62). All participants completed the Health Care Providers' Pain and Impairment Relationship Scale (range 15 to 105). This questionnaire measures attitudes towards functioning in individuals with back pain. Fourth year physiotherapy students had more positive attitudes towards functioning in individuals with back pain than first year physiotherapy students [57.4 vs 66.6 (mean difference -9.2, 95% confidence interval -12.2 to -6.1, P<0.01)]. Similarly, fourth year non-healthcare students had more positive attitudes towards functioning in individuals with back pain compared with first year non-healthcare students [69.2 vs 65.3 (mean difference -3.9, 95% confidence interval -7.2 to -0.5, P=0.03)]. Physiotherapy students had more positive attitudes than non-healthcare students in the first year [66.6 vs 69.2 (mean difference -2.6, 95% confidence interval -5.5 to 0.4, P=0.08)] and the fourth year [57.4 vs 65.3 (mean difference -7.9, 95% confidence interval -11.4 to -4.4, P<0.01)] of study. These findings suggest that physiotherapy education brings about positive student attitudes towards functioning in individuals with back pain. This may be partly attributable to receiving a university degree education, but would appear to be further enhanced by specifically receiving a physiotherapy degree. This may facilitate students to become more evidence-based practitioners following qualification. Copyright 2009 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

Observed sensitivity during family interactions and cumulative risk: A study of multiple dyads per family.

PubMed

Browne, Dillon T; Leckie, George; Prime, Heather; Perlman, Michal; Jenkins, Jennifer M

2016-07-01

The present study sought to investigate the family, individual, and dyad-specific contributions to observed cognitive sensitivity during family interactions. Moreover, the influence of cumulative risk on sensitivity at the aforementioned levels of the family was examined. Mothers and 2 children per family were observed interacting in a round robin design (i.e., mother-older sibling, mother younger-sibling and sibling-dyad, N = 385 families). Data were dyadic, in that there were 2 directional scores per interaction, and were analyzed using a multilevel formulation of the Social Relations Model. Variance partitioning revealed that cognitive sensitivity is simultaneously a function of families, individuals and dyads, though the importance of these components varies across family roles. Cognitive sensitivity for mothers was primarily attributable to individual differences, whereas cognitive sensitivity for children was predominantly attributable to family and dyadic differences, especially for youngest children. Cumulative risk explained family and individual variance in cognitive sensitivity, particularly when actors were older or in a position of relative competence or authority (i.e., mother to children, older to younger siblings). Overall, this study demonstrates that cognitive sensitivity operates across levels of family organization, and is negatively impacted by psychosocial risk. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

A tale of agriculturalists and hunter-gatherers: Exploring the thrifty genotype hypothesis in native South Americans.

PubMed

Reales, Guillermo; Rovaris, Diego L; Jacovas, Vanessa C; Hünemeier, Tábita; Sandoval, José R; Salazar-Granara, Alcibiades; Demarchi, Darío A; Tarazona-Santos, Eduardo; Felkl, Aline B; Serafini, Michele A; Salzano, Francisco M; Bisso-Machado, Rafael; Comas, David; Paixão-Côrtes, Vanessa R; Bortolini, Maria Cátira

2017-07-01

To determine genetic differences between agriculturalist and hunter-gatherer southern Native American populations for selected metabolism-related markers and to test whether Neel's thrifty genotype hypothesis (TGH) could explain the genetic patterns observed in these populations. 375 Native South American individuals from 17 populations were genotyped using six markers (APOE rs429358 and rs7412; APOA2 rs5082; CD36 rs3211883; TCF7L2 rs11196205; and IGF2BP2 rs11705701). Additionally, APOE genotypes from 39 individuals were obtained from the literature. AMOVA, main effects, and gene-gene interaction tests were performed. We observed differences in allele distribution patterns between agriculturalists and hunter-gatherers for some markers. For instance, between-groups component of genetic variance (F CT ) for APOE rs429358 showed strong differences in allelic distributions between hunter-gatherers and agriculturalists (p = 0.00196). Gene-gene interaction analysis indicated that the APOE E4/CD36 TT and APOE E4/IGF2BP2 A carrier combinations occur at a higher frequency in hunter-gatherers, but this combination is not replicated in archaic (Neanderthal and Denisovan) and ancient (Anzick, Saqqaq, Ust-Ishim, Mal'ta) hunter-gatherer individuals. A complex scenario explains the observed frequencies of the tested markers in hunter-gatherers. Different factors, such as pleotropic alleles, rainforest selective pressures, and population dynamics, may be collectively shaping the observed genetic patterns. We conclude that although TGH seems a plausible hypothesis to explain part of the data, other factors may be important in our tested populations. © 2017 Wiley Periodicals, Inc.

Japanese population structure, based on SNP genotypes from 7003 individuals compared to other ethnic groups: effects on population-based association studies.

PubMed

Yamaguchi-Kabata, Yumi; Nakazono, Kazuyuki; Takahashi, Atsushi; Saito, Susumu; Hosono, Naoya; Kubo, Michiaki; Nakamura, Yusuke; Kamatani, Naoyuki

2008-10-01

Because population stratification can cause spurious associations in case-control studies, understanding the population structure is important. Here, we examined Japanese population structure by "Eigenanalysis," using the genotypes for 140,387 SNPs in 7003 Japanese individuals, along with 60 European, 60 African, and 90 East-Asian individuals, in the HapMap project. Most Japanese individuals fell into two main clusters, Hondo and Ryukyu; the Hondo cluster includes most of the individuals from the main islands in Japan, and the Ryukyu cluster includes most of the individuals from Okinawa. The SNPs with the greatest frequency differences between the Hondo and Ryukyu clusters were found in the HLA region in chromosome 6. The nonsynonymous SNPs with the greatest frequency differences between the Hondo and Ryukyu clusters were the Val/Ala polymorphism (rs3827760) in the EDAR gene, associated with hair thickness, and the Gly/Ala polymorphism (rs17822931) in the ABCC11 gene, associated with ear-wax type. Genetic differentiation was observed, even among different regions in Honshu Island, the largest island of Japan. Simulation studies showed that the inclusion of different proportions of individuals from different regions of Japan in case and control groups can lead to an inflated rate of false-positive results when the sample sizes are large.

Group engagement in persons with dementia: The concept and its measurement.

PubMed

Cohen-Mansfield, Jiska; Hai, Tasmia; Comishen, Michael

2017-05-01

Although a few papers documented benefits of group therapeutic activities for individuals with dementia, there is a dearth of studies that have investigated the effects of group activities on persons with dementia. This paper introduces a theoretical framework of studying group therapeutic recreational activity, the Comprehensive Process Model of Group Engagement, and an assessment tool, the Group Observational Measurement of Engagement (GOME). We also report the psychometric properties of this assessment. One hundred and four persons with dementia took part in ten different group activities, with each activity conducted twice at random order so that 20 activities were observed for each group of participants. Following each group activity, research and therapeutic recreation staff members used the GOME assessment to independently rate participants on individual-level measures of attendance duration and engagement, and group level measures (e.g., positive and negative interactions among group members). Reliability and validity analyses comparing observer ratings for each group activity on the individual-level measures of attendance and engagement showed good psychometric properties. Different measures collected on a group level differed with respect to their psychometric quality. We present a theoretical framework to understand group engagement and present measures that could be used in future research and practice. Copyright © 2017 Elsevier Ireland Ltd. All rights reserved.

Pollen donor composition during the early phases of reproduction revealed by DNA genotyping of pollen grains and seeds of Castanea crenata.

PubMed

Hasegawa, Yoichi; Suyama, Yoshihisa; Seiwa, Kenji

2009-06-01

In plants, pollen donor composition can differ during the early phases of reproduction through various selection mechanisms favouring self, related or nonrelated pollen donors, but such differences have not been examined under natural conditions because paternity is difficult to analyse in a natural setting. Here, we performed paternity analyses based on microsatellite genotyping of individual pollen grains deposited on female flowers (n = 773) and seeds (n = 304) to evaluate pollen donor composition from three individuals of the insect-pollinated monoecious tree Castanea crenata in a natural forest. Spatial genetic structure was also investigated. A mean self-pollen rate of 90.2% was observed at the pollination stage, but a low selfing rate of 0.3% was observed at the seed stage. In outcross events, however, pairwise distance and relatedness between maternal and paternal parents were not different between pollination and seed stages. We also observed significant positive relatedness, based on clear fine-scale genetic structure of individual trees within 80 m of one another, and 71% of seeds were derived using pollen grains of related trees within 80 m. The results suggest that the mechanism of self-incompatibility strongly avoids self-pollen before seed production. However, the avoidance of biparental inbreeding was not obvious between pollination and seed stages.

The role of social attraction and its link with boldness in the collective movements of three-spined sticklebacks.

PubMed

Jolles, Jolle W; Fleetwood-Wilson, Adeline; Nakayama, Shinnosuke; Stumpe, Martin C; Johnstone, Rufus A; Manica, Andrea

2015-01-01

Social animals must time and coordinate their behaviour to ensure the benefits of grouping, resulting in collective movements and the potential emergence of leaders and followers. However, individuals often differ consistently from one another in how they cope with their environment, a phenomenon known as animal personality, which may affect how individuals use coordination rules and requiring them to compromise. Here we tracked the movements of pairs of three-spined sticklebacks, Gasterosteus aculeatus , separated by a transparent partition that allowed them to observe and interact with one another in a context containing cover. Individuals differed consistently in their tendency to approach their partner's compartment during collective movements. The strength of this social attraction was positively correlated with the behavioural coordination between members of a pair but was negatively correlated with an individual's tendency to lead. Social attraction may form part of a broader behavioural syndrome as it was predicted by the boldness of an individual, measured in isolation prior to the observation of pairs, and by the boldness of the partner. We found that bolder fish, and those paired with bolder partners, tended to approach their partner's compartment less closely. These findings provide important insights into the mechanisms that govern the dynamics and functioning of social groups and the emergence and maintenance of consistent behavioural differences.

The role of social attraction and its link with boldness in the collective movements of three-spined sticklebacks

PubMed Central

Jolles, Jolle W.; Fleetwood-Wilson, Adeline; Nakayama, Shinnosuke; Stumpe, Martin C.; Johnstone, Rufus A.; Manica, Andrea

2015-01-01

Social animals must time and coordinate their behaviour to ensure the benefits of grouping, resulting in collective movements and the potential emergence of leaders and followers. However, individuals often differ consistently from one another in how they cope with their environment, a phenomenon known as animal personality, which may affect how individuals use coordination rules and requiring them to compromise. Here we tracked the movements of pairs of three-spined sticklebacks, Gasterosteus aculeatus, separated by a transparent partition that allowed them to observe and interact with one another in a context containing cover. Individuals differed consistently in their tendency to approach their partner's compartment during collective movements. The strength of this social attraction was positively correlated with the behavioural coordination between members of a pair but was negatively correlated with an individual's tendency to lead. Social attraction may form part of a broader behavioural syndrome as it was predicted by the boldness of an individual, measured in isolation prior to the observation of pairs, and by the boldness of the partner. We found that bolder fish, and those paired with bolder partners, tended to approach their partner's compartment less closely. These findings provide important insights into the mechanisms that govern the dynamics and functioning of social groups and the emergence and maintenance of consistent behavioural differences. PMID:25598543

Extrapunitive and Intropunitive Individuals Activate Different Parts of the Prefrontal Cortex under an Ego-Blocking Frustration

PubMed Central

Minamoto, Takehiro; Osaka, Mariko; Yaoi, Ken; Osaka, Naoyuki

2014-01-01

Different people make different responses when they face a frustrating situation: some punish others (extrapunitive), while others punish themselves (intropunitive). Few studies have investigated the neural structures that differentiate extrapunitive and intropunitive individuals. The present fMRI study explored these neural structures using two different frustrating situations: an ego-blocking situation which blocks a desire or goal, and a superego-blocking situation which blocks self-esteem. In the ego-blocking condition, the extrapunitive group (n = 9) showed greater activation in the bilateral ventrolateral prefrontal cortex, indicating that these individuals prefer emotional processing. On the other hand, the intropunitive group (n = 9) showed greater activation in the left dorsolateral prefrontal cortex, possibly reflecting an effortful control for anger reduction. Such patterns were not observed in the superego-blocking condition. These results indicate that the prefrontal cortex is the source of individual differences in aggression direction in the ego-blocking situation. PMID:24454951

Lack of validation of the Dixtal (DX 2020) upper arm blood pressure monitor, in oscillometric mode, for clinical use in an intensive care unit, according to the European Society of Hypertension-International Protocol revision 2010.

PubMed

Gothardo, Ana C L O; Savioli, Amanda F; Santos, Dayanna S; Lamas, José L T

2013-08-01

The aim of the study was to evaluate the accuracy of the oscillometric blood pressure section in the DX 2020 Dixtal multiparametric monitor in adults according to the European Society of Hypertension-International Protocol as revised in 2010 (ESH-IP 2010). The blood pressure was sequentially verified in 33 individuals admitted to an adult ICU (18 men, mean age 44 years) with a mercury column sphygmomanometer (two observers) and the DX 2020 test device (one supervisor). Ninety-nine pairs of differences were obtained. Data analysis followed the ESH-IP 2010 requirements. In the first requirement, the DX 2020 device failed in the validation study in the 5, 10, and 15 mmHg ranges. From the 99 pairs of differences, only 43/73, 69/87, and 81/96 were obtained for systolic blood pressure and 29/65, 56/81, and 71/93 were obtained for diastolic blood pressure. In the second requirement, at least 24 individuals should have, from their comparisons, two under 0-5 mmHg ranges, which was observed only with 16 individuals in the systolic and nine in the diastolic range. Moreover, at maximum, only three readings could have differences of more than 5 mmHg, and this was observed in 10 individuals in the systolic range and 17 individuals in the diastolic range. The DX 2020 automatic multiparametric monitor for blood pressure measurement has not been recommended for clinical use according to the ESH-IP 2010. It is important to highlight that this work refers only to a blood pressure measurement module and that the same conclusion cannot be drawn for its other functions.

Facilitatory non-invasive brain stimulation in older adults: the effect of stimulation type and duration on the induction of motor cortex plasticity.

PubMed

Puri, Rohan; Hinder, Mark R; Canty, Alison J; Summers, Jeffery J

2016-12-01

Despite holding significant promise for counteracting the deleterious effects of ageing on cognitive and motor function, little is known of the effects of facilitatory non-invasive brain stimulation (NBS) techniques on corticospinal excitability (CSE) in older adults. Thirty-three older adults (≥60 years) participated in four NBS sessions on separate days, receiving 10- and 20-min anodal transcranial direct current stimulation (atDCS), and 300 and 600 pulses of intermittent theta burst stimulation (iTBS) over the left M1. Motor-evoked potentials measured in the contralateral hand served as a measure of CSE before and for 30 min following each NBS intervention. At the group level, generalized post-stimulation CSE increases were observed (p < 0.001) with no significant differences between the two durations of each stimulation type (atDCS: p = 0.5; iTBS: p = 0.9). For individuals exhibiting overall facilitatory change to atDCS ('responders', n = 10), 20-min atDCS resulted in longer lasting CSE facilitation than 10 min. No such difference was observed between the two iTBS protocols. Considerable variability was observed inter-individually, where 52-58 % of the cohort exhibited the expected facilitation after each of the NBS protocols-as well as intra-individually, where 45-48 % of the cohort maintained consistent post-stimulation responses across the varying durations and types of stimulation. In conclusion, as shown previously in young adults, older adults demonstrate substantial variability in response to different facilitatory NBS protocols. Studies to assess the intra-individual reliability of these protocols are critical to progress towards translation of appropriate protocols (i.e. those that elicit the greatest response for each individual) into clinical practice.

The Evolution of Homophily

NASA Astrophysics Data System (ADS)

Fu, Feng; Nowak, Martin A.; Christakis, Nicholas A.; Fowler, James H.

2012-11-01

Biologists have devoted much attention to assortative mating or homogamy, the tendency for sexual species to mate with similar others. In contrast, there has been little theoretical work on the broader phenomenon of homophily, the tendency for individuals to interact with similar others. Yet this behaviour is also widely observed in nature. Here, we model how natural selection can give rise to homophily when individuals engage in social interaction in a population with multiple observable phenotypes. Payoffs to interactions depend on whether or not individuals have the same or different phenotypes, and each individual has a preference that determines how likely they are to interact with others of their own phenotype (homophily) or of opposite phenotypes (heterophily). The results show that homophily tends to evolve under a wide variety of conditions, helping to explain its ubiquity in nature.

The dynamics of social networks among female Asian elephants

PubMed Central

2011-01-01

Background Patterns in the association of individuals can shed light on the underlying conditions and processes that shape societies. Here we characterize patterns of association in a population of wild Asian Elephants at Uda Walawe National Park in Sri Lanka. We observed 286 individually-identified adult female elephants over 20 months and examined their social dynamics at three levels of organization: pairs of individuals (dyads), small sets of direct companions (ego-networks), and the population level (complete networks). Results Corroborating previous studies of this and other Asian elephant populations, we find that the sizes of elephant groups observed in the field on any particular day are typically small and that rates of association are low. In contrast to earlier studies, our longitudinal observations reveal that individuals form larger social units that can be remarkably stable across years while associations among such units change across seasons. Association rates tend to peak in dry seasons as opposed to wet seasons, with some cyclicity at the level of dyads. In addition, we find that individuals vary substantially in their fidelity to companions. At the ego-network level, we find that despite these fluctuations, individuals associate with a pool of long-term companions. At the population level, social networks do not exhibit any clear seasonal structure or hierarchical stratification. Conclusions This detailed longitudinal study reveals different social dynamics at different levels of organization. Taken together, these results demonstrate that low association rates, seemingly small group sizes, and fission-fusion grouping behavior mask hidden stability in the extensive and fluid social affiliations in this population of Asian elephants. PMID:21794147

Sleep-wake differences in scaling behavior of the human heartbeat: analysis of terrestrial and long-term space flight data

NASA Technical Reports Server (NTRS)

Bunde, A.; Amaral, L. A.; Havlin, S.; Fritsch-Yelle, J.; Baevsky, R. M.; Stanley, H. E.; Goldberger, A. L.

1999-01-01

We compare scaling properties of the cardiac dynamics during sleep and wake periods for healthy individuals, cosmonauts during orbital flight, and subjects with severe heart disease. For all three groups, we find a greater degree of anticorrelation in the heartbeat fluctuations during sleep compared to wake periods. The sleep-wake difference in the scaling exponents for the three groups is comparable to the difference between healthy and diseased individuals. The observed scaling differences are not accounted for simply by different levels of activity, but appear related to intrinsic changes in the neuroautonomic control of the heartbeat.

Phototactic personality in fruit flies and its suppression by serotonin and white.

PubMed

Kain, Jamey S; Stokes, Chris; de Bivort, Benjamin L

2012-11-27

Drosophila typically move toward light (phototax positively) when startled. The various species of Drosophila exhibit some variation in their respective mean phototactic behaviors; however, it is not clear to what extent genetically identical individuals within each species behave idiosyncratically. Such behavioral individuality has indeed been observed in laboratory arthropods; however, the neurobiological factors underlying individual-to-individual behavioral differences are unknown. We developed "FlyVac," a high-throughput device for automatically assessing phototaxis in single animals in parallel. We observed surprising variability within every species and strain tested, including identically reared, isogenic strains. In an extreme example, a domesticated strain of Drosophila simulans harbored both strongly photopositive and strongly photonegative individuals. The particular behavior of an individual fly is not heritable and, because it persists for its lifetime, constitutes a model system for elucidating the molecular mechanisms of personality. Although all strains assayed had greater than expected variation (assuming binomial sampling), some had more than others, implying a genetic basis. Using genetics and pharmacology, we identified the metabolite transporter White and white-dependent serotonin as suppressors of phototactic personality. Because we observed behavioral idiosyncrasy in all experimental groups, we suspect it is present in most behaviors of most animals.

All individuals are not created equal; accounting for interindividual variation in fitting life-history responses to toxicants.

PubMed

Jager, Tjalling

2013-02-05

The individuals of a species are not equal. These differences frustrate experimental biologists and ecotoxicologists who wish to study the response of a species (in general) to a treatment. In the analysis of data, differences between model predictions and observations on individual animals are usually treated as random measurement error around the true response. These deviations, however, are mainly caused by real differences between the individuals (e.g., differences in physiology and in initial conditions). Understanding these intraspecies differences, and accounting for them in the data analysis, will improve our understanding of the response to the treatment we are investigating and allow for a more powerful, less biased, statistical analysis. Here, I explore a basic scheme for statistical inference to estimate parameters governing stress that allows individuals to differ in their basic physiology. This scheme is illustrated using a simple toxicokinetic-toxicodynamic model and a data set for growth of the springtail Folsomia candida exposed to cadmium in food. This article should be seen as proof of concept; a first step in bringing more realism into the statistical inference for process-based models in ecotoxicology.

Differences and effects of medium and large adult cuffs on blood pressure readings in individuals with muscular arms.

PubMed

Fonseca-Reyes, Salvador; Fajardo-Flores, Ismael; Montes-Casillas, Mayra; Forsyth-Macquarrie, Avril

2009-08-01

This study analyzed systolic and diastolic blood pressure (SBP and DBP) reading differences in individuals with muscular arms, using medium and large adult cuffs. Resting blood pressures (BPs) were measured in bodybuilders competing at the Mexican National Bodybuilding and Fitness Championship. The means of two bilateral simultaneous arm BP measurements were obtained using two different cuff sizes, 12 cm (medium adult) and 16 cm (large adult). A total of 193 bodybuilders completed the measurements. With an arm circumference greater than 33 cm, the SBP and DBP average taken with the medium adult cuff was higher than that obtained with the large adult cuff, 8.2+/-10.6 and 1.6+/-7.4 mmHg, respectively; however, a significant difference was observed only with the SBP. With the medium adult cuff, 48 of 144 individuals showed SBP at least 140 mmHg, whereas with the large adult cuff there were only 17 of 144 individuals. In those participants with an arm circumference less than 33 cm, the BP was nonsignificantly lower with the large cuff, -4.24+/-9.2 and -2.24+/-5.4 mmHg for the SBP and DBP, respectively. Incorrect cuffing of a muscular arm leads to significant errors in the measurement of SBP and DBP, similar to that observed in miscuffing of nonmuscular arms.

Studies on avian malaria in vectors and hosts of encephalitis in Kern County, California. I. Infections in avian hosts

USGS Publications Warehouse

Herman, C.M.; Reeves, W.C.; McClure, H.E.; French, E.M.; Hammon, W.M.

1954-01-01

An epizoological study of Plasmodium infections in wild birds of Kern County, California, in the years 1946 through 1951 greatly extended knowledge of the occurrence of these parasites and their behavior in nature. Examination of 10,459 blood smears from 8,674 birds representing 73 species resulted in the observation of Plasmodium spp. in 1,094 smears representing 888 individual birds of 27 species. Seven species of Plasmodium were found: relictum, elongatum, hexamerium, nucleophilum, polare, rouxi and vaughani. Plasmodium relictum was by far the most frequently observed species, occurring in at least 79 per cent of the infected birds. Twelve new host species are recorded for this parasite. Sufficient morphological variation was observed to indicate that two strains of this species probably exist in nature. Numerous new host records were made of plasmodia with elongate gametocytes. The finding of parasites believed to be P. rouxi in two new host species represents the first record of the occurrence of this Plasmodium outside of Algeria. Multiple smears were obtained from a number of individual birds over varying time periods. Evidence of prolonged parasitemia was unusual, but some individuals had parasitemia on consecutive months and even for three successive years. In most individuals, parasitemias were of short duration. The inoculation of blood from wild birds into canaries led to the demonstration of many infections not observed on blood smear examination of donors. Use of these two complementary techniques led to more complete host records and a truer picture of the prevalence of infection. Three age classes of birds were studied--nestling, immature (less than 1 year of age) and adult. Parasites were observed in all three groups but infections in the younger individuals were most susceptible to interpretation. As to time of onset, numerous records were obtained of infection in nestling birds. Prevalence rates in immature birds after a single season's exposure ranged from 64 to 100 per cent in the house finch and 17 to 68 per cent in the English sparrow in different areas and years. Marked differences were found in the prevalence rates in different summer months, years and areas. It is believed these differences reflect variation in a number of environmental factors. This study indicates the extensive distribution of Plasmodium infection in a wide range of wild avian hosts. The observations are of possible importance in epidemiological studies of other arthropod-borne diseases such as the viral encephalitides for which these birds serve as hosts.

Species rarity: definition, causes, and classification

Treesearch

Curtis H. Flather; Carolyn Hull Sieg

2007-01-01

In virtually all ecological communities around the world, most species are represented by few individuals, and most individuals come from only a few of the most common species. Why this distribution of species abundances is so regularly observed among different taxonomic sets in geographically diverse systems is a question that has received considerable theoretical and...

[Inferential evaluation of intimacy based on observation of interpersonal communication].

PubMed

Kimura, Masanori

2015-06-01

How do people inferentially evaluate others' levels of intimacy with friends? We examined the inferential evaluation of intimacy based on the observation of interpersonal communication. In Experiment 1, participants (N = 41) responded to questions after observing conversations between friends. Results indicated that participants inferentially evaluated not only goodness of communication, but also intimacy between friends, using an expressivity heuristic approach. In Experiment 2, we investigated how inferential evaluation of intimacy was affected by prior information about relationships and by individual differences in face-to-face interactional ability. Participants (N = 64) were divided into prior- and no-prior-information groups and all performed the same task as in Experiment 1. Additionally, their interactional ability was assessed. In the prior-information group, individual differences had no effect on inferential evaluation of intimacy. On the other hand, in the no-prior-information group, face-to-face interactional ability partially influenced evaluations of intimacy. Finally, we discuss the fact that to understand one's social environment, it is important to observe others' interpersonal communications.

Comparison of Efficacy and Safety of Liraglutide 3.0 mg in Individuals with BMI above and below 35 kg/m²: A Post-hoc Analysis

PubMed Central

le Roux, Carel; Aroda, Vanita; Hemmingsson, Joanna; Cancino, Ana Paula; Christensen, Rune; Pi-Sunyer, Xavier

2018-01-01

Objective To investigate whether the efficacy and safety of liraglutide 3.0 mg differed between two subgroups, BMI 27 to <35 and BMI ≥ 35 kg/m², in individuals without and with type 2 diabetes (T2D). Methods A post-hoc analysis of two 56-week, randomized, double-blind, placebo-controlled trials (SCALE Obesity and Prediabetes; SCALE Diabetes). Subgroup differences in treatment effects of liraglutide 3.0 mg were evaluated by testing the interaction between treatment group and baseline BMI subgroup. Results Significantly greater weight loss (0–56 weeks) was observed with liraglutide 3.0 mg versus placebo in all patient groups while on treatment. There was no evidence that the weight-lowering effect of liraglutide 3.0 mg differed between BMI subgroups (interaction p > 0.05). Similarly, for most secondary endpoints significantly greater improvements were observed with liraglutide 3.0 mg versus placebo, with no indication treatment effects differing between subgroups. The safety profile of liraglutide 3.0 mg was broadly similar across BMI subgroups. Conclusion This post-hoc analysis did not indicate any differences in the treatment effects, or safety profile, of liraglutide 3.0 mg for individuals with BMI 27 to <35 or ≥35 kg/m². Liraglutide 3.0 mg can therefore be considered for individuals with a BMI of ≥35 as well as for those with a BMI of 27 to <35 kg/m². PMID:29145215

Lack of color integration in visual short-term memory binding.

PubMed

Parra, Mario A; Cubelli, Roberto; Della Sala, Sergio

2011-10-01

Bicolored objects are retained in visual short-term memory (VSTM) less efficiently than unicolored objects. This is unlike shape-color combinations, whose retention in VSTM does not differ from that observed for shapes only. It is debated whether this is due to a lack of color integration and whether this may reflect the function of separate memory mechanisms. Participants judged whether the colors of bicolored objects (each with an external and an internalcolor) were the same or different across two consecutive screens. Colors had to be remembered either individually or in combination. In Experiment 1, external colors in the combined colors condition were remembered better than the internal colors, and performance for both was worse than that in the individual colors condition. The lack of color integration observed in Experiment 1 was further supported by a reduced capacity of VSTM to retain color combinations, relative to individual colors (Experiment 2). An additional account was found in Experiment 3, which showed spared color-color binding in the presence of impaired shape-color binding in a brain-damaged patient, thus suggesting that these two memory mechanisms are different.

Force-velocity property of leg muscles in individuals of different level of physical fitness.

PubMed

Cuk, Ivan; Mirkov, Dragan; Nedeljkovic, Aleksandar; Kukolj, Milos; Ugarkovic, Dusan; Jaric, Slobodan

2016-06-01

The present study explored the method of testing muscle mechanical properties through the linear force-velocity (F-V) relationships obtained from loaded vertical jumps. Specifically, we hypothesised that the F-V relationship parameters depicting the force, power, and velocity of the tested muscles will differ among individuals of different physical fitness. Strength trained, physically active, and sedentary male participants (N = 10 + 10 + 10; age 20-29 years) were tested on maximum countermovement and squat jumps where manipulation of external loads provided a range of F and V data. The observed F-V relationships of the tested leg muscles were approximately linear and mainly strong (median correlation coefficients ranged from 0.77 to 0.92; all p < 0.05), independently of either the tested group or the jump type. The maximum power revealed higher values in the strength trained than in the physically active and sedentary participants. This difference originated from the differences in F-intercepts, rather than from the V-intercepts. We conclude that the observed parameters could be sensitive enough to detect the differences among both the individuals of different physical fitness and various jump types. The present findings support using loaded vertical jumps and, possibly, other maximum performance multi-joint movements for the assessment of mechanical properties of active muscles.

Mobile genes in the human microbiome are structured from global to individual scales

PubMed Central

Brito, IL; Jupiter, SD; Jenkins, AP; Naisilisili, W; Tamminen, M; Smillie, CS; Wortman, JR; Birren, BW; Xavier, RJ; Blainey, PC; Singh, AK; Gevers, D; Alm, EJ

2016-01-01

Recent work has underscored the importance of the microbiome in human health, largely attributing differences in phenotype to differences in the species present across individuals1,2,3,4,5. But mobile genes can confer profoundly different phenotypes on different strains of the same species. Little is known about the function and distribution of mobile genes in the human microbiome, and in particular whether the gene pool is globally homogenous or constrained by human population structure. Here, we investigate this question by comparing the mobile genes found in the microbiomes of 81 metropolitan North Americans with that of 172 agrarian Fiji islanders using a combination of single-cell genomics and metagenomics. We find large differences in mobile gene content between the Fijian and North American microbiomes, with functional variation that mirrors known dietary differences such as the excess of plant-based starch degradation genes. Remarkably, differences are also observed between the mobile gene pools of proximal Fijian villages, even though microbiome composition across villages is similar. Finally, we observe high rates of recombination leading to individual-specific mobile elements, suggesting that the abundance of some genes may reflect environmental selection rather than dispersal limitation. Together, these data support the hypothesis that human activities and behaviors provide selective pressures that shape mobile gene pools, and that acquisition of mobile genes is important to colonizing specific human populations. PMID:27409808

Country of origin and bariatric surgery in Sweden during 2001–2010

PubMed Central

Memarian, Ensieh; Sundquist, Kristina; Calling, Susanna; Sundquist, Jan; Li, Xinjun

2016-01-01

Background The prevalence of obesity, as well as use of bariatric surgery, has increased worldwide. The aim of the present study was to investigate the potential differences in the use of bariatric surgery among Swedes and immigrants in Sweden and whether the hypothesized differences remain after adjustment for socioeconomic factors. Methods A closed cohort of all individuals aged 20–64 years was followed during 2001–2010. Further analyses were performed in 2 periods separately (2001–2005 and 2006–2010). Age-standardized cumulative incidence rates (CR) of bariatric surgery were compared between Swedes and immigrants considering individual variables. Cox proportional hazards models were used in univariate and multivariate models for males and females. Results A total of 12,791 Swedes and 2060 immigrants underwent bariatric surgery. The lowest rates of bariatric surgery were found in immigrant men. The largest difference in CR between Swedes and immigrants was observed among low-income individuals (3.4 and 2.3 per 1000 individuals, respectively). Adjusted hazard ratios (HRs) were lower for all immigrants compared with Swedes in the second period. The highest HRs were observed among immigrants from Chile and Lebanon and the lowest among immigrants from Bosnia. Except for Nordic countries, immigrants from all other European countries had a lower HR compared with Swedes. Conclusions Men in general and some immigrant groups had a lower HR of bariatric surgery. Moreover, the difference between Swedes and immigrants was more pronounced in individuals with low socioeconomic status (income). It is unclear if underlying barriers to receive bariatric surgery are due to patients’ preferences/lack of knowledge or healthcare structures. Future studies are needed to examine potential causes behind these differences. PMID:25979207

Country of origin and bariatric surgery in Sweden during 2001-2010.

PubMed

Memarian, Ensieh; Sundquist, Kristina; Calling, Susanna; Sundquist, Jan; Li, Xinjun

2015-01-01

The prevalence of obesity, as well as use of bariatric surgery, has increased worldwide. The aim of the present study was to investigate the potential differences in the use of bariatric surgery among Swedes and immigrants in Sweden and whether the hypothesized differences remain after adjustment for socioeconomic factors. A closed cohort of all individuals aged 20-64 years was followed during 2001-2010. Further analyses were performed in 2 periods separately (2001-2005 and 2006-2010). Age-standardized cumulative incidence rates (CR) of bariatric surgery were compared between Swedes and immigrants considering individual variables. Cox proportional hazards models were used in univariate and multivariate models for males and females. A total of 12,791 Swedes and 2060 immigrants underwent bariatric surgery. The lowest rates of bariatric surgery were found in immigrant men. The largest difference in CR between Swedes and immigrants was observed among low-income individuals (3.4 and 2.3 per 1000 individuals, respectively). Adjusted hazard ratios (HRs) were lower for all immigrants compared with Swedes in the second period. The highest HRs were observed among immigrants from Chile and Lebanon and the lowest among immigrants from Bosnia. Except for Nordic countries, immigrants from all other European countries had a lower HR compared with Swedes. Men in general and some immigrant groups had a lower HR of bariatric surgery. Moreover, the difference between Swedes and immigrants was more pronounced in individuals with low socioeconomic status (income). It is unclear if underlying barriers to receive bariatric surgery are due to patients' preferences/lack of knowledge or healthcare structures. Future studies are needed to examine potential causes behind these differences. Copyright © 2015 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

Effects of context and individual differences on the processing of taboo words.

PubMed

Christianson, Kiel; Zhou, Peiyun; Palmer, Cassie; Raizen, Adina

2017-07-01

Previous studies suggest that taboo words are special in regards to language processing. Findings from the studies have led to the formation of two theories, global resource theory and binding theory, of taboo word processing. The current study investigates how readers process taboo words embedded in sentences during silent reading. In two experiments, measures collected include eye movement data, accuracy and reaction time measures for recalling probe words within the sentences, and individual differences in likelihood of being offended by taboo words. Although certain aspects of the results support both theories, as the likelihood of a person being offended by a taboo word influenced some measures, neither theory sufficiently predicts or describes the effects observed. The results are interpreted as evidence that processing effects ascribed to taboo words are largely, but not completely, attributable to the context in which they are used and the individual attitudes of the people who hear/read them. The results also demonstrate the importance of investigating taboo words in naturalistic language processing paradigms. A revised theory of taboo word processing is proposed that incorporates both global resource theory and binding theory along with the sociolinguistic factors and individual differences that largely drive the effects observed here. Copyright © 2017 Elsevier B.V. All rights reserved.

Nonadverse effects on allergenicity of isopentenyltransferase-transformed broccoli.

PubMed

Liao, E C; Chen, J T; Chao, M L; Yu, S C; Chang, C Y; Chu, W S; Tsai, J J

2013-01-01

Genetically modified organisms (GMOs) provide modern agriculture with improvements in efficiency and the benefits of enhanced food production; however, the potential impact of GMOs on human health has not yet been clarified. To investigate the allergenicity of isopentenyltransferase (ipt)-transformed broccoli compared with non-GM broccoli. Sera from allergic individuals were used to identify the allergenicity of GM and non-GM broccoli. Immunoglobulin (Ig) binding of different lines of GM and non-GM broccoli was identified using immunoblotting, enzyme-linked immunosorbent assay, and the histamin release assay. Positive reactions to broccoli (Brassica Oleracea) were observed in 7.02% of individuals. Specific IgE to broccoli and total IgE fro allergic individuals were well correlated. The different tests performed showed no significant differences in the allergenicity of conventionally raised and GM broccoli, indicating the absence of unexpected effects on allergenicity in ipt-transformed plants. Using Western blot analysis we detected heterogeneous IgE-reactive allergenic components in broccoli-allergic sera, but no significant differences between GM an non-GM broccoli were observed in serum from the same patients. Our study demonstrates that there are no differences between GM (ipt-transformed) broccoli and non-GM broccoli, as determined by specific IgE in sera from broccoli-allergic patients. This indicates that there were no unexpected effects on allergenicity in this GM broccoli.

Morphology of the tympanic-basicranial region in Mirounga leonina (Phocidae, Carnivora), postnatal ontogeny and sexual dimorphism

PubMed Central

Loza, C M; Scarano, A C; Soibelzon, L H; Negrete, J; Carlini, A A

2015-01-01

The auditory region of pinnipeds has seldom been described. Here we describe and analyze the ontogenetic trajectory of the tympanic bulla of the southern elephant seal, Mirounga leonina (Phocidae, Mammalia). This species is extremely sexually dimorphic and highly polygynous (organized in harems). We examined 118 specimens, arranged in three age classes (CI, CII, and CIII), ranging from newborn to adults (males and females). To analyze the overall size and shape of the tympanic bulla we performed a geometric morphometric analysis including 87 skulls. Females reach definitive shape and size of the bulla at earlier ontogenetic stages than males, in agreement with their earlier involvement in reproductive activities. The internal anatomy of the tympanic region (e.g. form and extension of the paries) does not show remarkable differences between sexes or age classes. The greatest differences between age classes are related to bone thickness, resulting from the apposition of new annual layers. An examination of possible sex-related external differences among age classes shows significant shape differences between males and females in CIII. The morphology observed in neonates is conserved across all individuals from CI, which included specimens up to 1 year old. Clear morphological differences were observed between CI individuals, on one hand, and CII individuals plus CIII females on the other. During cranial development of both male and females, the glenoid cavity expands and compresses the bulla; this condition reaches its maximum expression in CIII males. CIII males showed the greatest morphological differences, with respect to both CI and CII individuals, and CIII females. PMID:25827162

How training citizen scientists affects the accuracy and precision of phenological data

NASA Astrophysics Data System (ADS)

Feldman, Richard E.; Žemaitė, Irma; Miller-Rushing, Abraham J.

2018-05-01

Monitoring plant and animal phenology is a critical step to anticipating and predicting changes in species interactions and biodiversity. Because phenology necessarily involves frequent and repeated observations over time, citizen scientists have become a vital part of collecting phenological data. However, there is still concern over the accuracy and precision of citizen science data. It is possible that training citizen scientists can improve data quality though there are few comparisons of trained and untrained citizen scientists in the ability of each to accurately and precisely measure phenology. We assessed how three types of observers—experts, trained citizen scientists that make repeated observations, and untrained citizen scientists making once-per-year observations—differ in quantifying temporal change in flower and fruit abundance of American mountain ash trees (Sorbus americana Marsh.) and arthropods in Acadia National Park, Maine, USA. We found that trained more so than untrained citizen science observers over- or under-estimated abundances leading to precise but inaccurate characterizations of phenological patterns. Our results suggest a new type of bias induced by repeated observations: A type of learning takes place that reduces the independence of observations taken on different trees or different dates. Thus, in this and many other cases, having individuals make one-off observations of marked plants may produce data as good if not better than individuals making repeated observations. For citizen science programs related to phenology, our results underscore the importance of (a) attracting the most number of observers possible even if they only make one observation, (b) producing easy-to-use and informative data sheets, and (c) carefully planning effective training programs that are, perhaps, repeated at different points during the data collection period.

Combining animal personalities with transcriptomics resolves individual variation within a wild-type zebrafish population and identifies underpinning molecular differences in brain function.

PubMed

Rey, S; Boltana, S; Vargas, R; Roher, N; Mackenzie, S

2013-12-01

Resolving phenotype variation within a population in response to environmental perturbation is central to understanding biological adaptation. Relating meaningful adaptive changes at the level of the transcriptome requires the identification of processes that have a functional significance for the individual. This remains a major objective towards understanding the complex interactions between environmental demand and an individual's capacity to respond to such demands. The interpretation of such interactions and the significance of biological variation between individuals from the same or different populations remain a difficult and under-addressed question. Here, we provide evidence that variation in gene expression between individuals in a zebrafish population can be partially resolved by a priori screening for animal personality and accounts for >9% of observed variation in the brain transcriptome. Proactive and reactive individuals within a wild-type population exhibit consistent behavioural responses over time and context that relates to underlying differences in regulated gene networks and predicted protein-protein interactions. These differences can be mapped to distinct regions of the brain and provide a foundation towards understanding the coordination of underpinning adaptive molecular events within populations. © 2013 John Wiley & Sons Ltd.

Probabilistic Inference: Task Dependency and Individual Differences of Probability Weighting Revealed by Hierarchical Bayesian Modeling

PubMed Central

Boos, Moritz; Seer, Caroline; Lange, Florian; Kopp, Bruno

2016-01-01

Cognitive determinants of probabilistic inference were examined using hierarchical Bayesian modeling techniques. A classic urn-ball paradigm served as experimental strategy, involving a factorial two (prior probabilities) by two (likelihoods) design. Five computational models of cognitive processes were compared with the observed behavior. Parameter-free Bayesian posterior probabilities and parameter-free base rate neglect provided inadequate models of probabilistic inference. The introduction of distorted subjective probabilities yielded more robust and generalizable results. A general class of (inverted) S-shaped probability weighting functions had been proposed; however, the possibility of large differences in probability distortions not only across experimental conditions, but also across individuals, seems critical for the model's success. It also seems advantageous to consider individual differences in parameters of probability weighting as being sampled from weakly informative prior distributions of individual parameter values. Thus, the results from hierarchical Bayesian modeling converge with previous results in revealing that probability weighting parameters show considerable task dependency and individual differences. Methodologically, this work exemplifies the usefulness of hierarchical Bayesian modeling techniques for cognitive psychology. Theoretically, human probabilistic inference might be best described as the application of individualized strategic policies for Bayesian belief revision. PMID:27303323

Muscle Force-Velocity Relationships Observed in Four Different Functional Tests.

PubMed

Zivkovic, Milena Z; Djuric, Sasa; Cuk, Ivan; Suzovic, Dejan; Jaric, Slobodan

2017-02-01

The aims of the present study were to investigate the shape and strength of the force-velocity relationships observed in different functional movement tests and explore the parameters depicting force, velocity and power producing capacities of the tested muscles. Twelve subjects were tested on maximum performance in vertical jumps, cycling, bench press throws, and bench pulls performed against different loads. Thereafter, both the averaged and maximum force and velocity variables recorded from individual trials were used for force-velocity relationship modeling. The observed individual force-velocity relationships were exceptionally strong (median correlation coefficients ranged from r = 0.930 to r = 0.995) and approximately linear independently of the test and variable type. Most of the relationship parameters observed from the averaged and maximum force and velocity variable types were strongly related in all tests (r = 0.789-0.991), except for those in vertical jumps (r = 0.485-0.930). However, the generalizability of the force-velocity relationship parameters depicting maximum force, velocity and power of the tested muscles across different tests was inconsistent and on average moderate. We concluded that the linear force-velocity relationship model based on either maximum or averaged force-velocity data could provide the outcomes depicting force, velocity and power generating capacity of the tested muscles, although such outcomes can only be partially generalized across different muscles.

Muscle Force-Velocity Relationships Observed in Four Different Functional Tests

PubMed Central

Zivkovic, Milena Z.; Djuric, Sasa; Cuk, Ivan; Suzovic, Dejan; Jaric, Slobodan

2017-01-01

Abstract The aims of the present study were to investigate the shape and strength of the force-velocity relationships observed in different functional movement tests and explore the parameters depicting force, velocity and power producing capacities of the tested muscles. Twelve subjects were tested on maximum performance in vertical jumps, cycling, bench press throws, and bench pulls performed against different loads. Thereafter, both the averaged and maximum force and velocity variables recorded from individual trials were used for force–velocity relationship modeling. The observed individual force-velocity relationships were exceptionally strong (median correlation coefficients ranged from r = 0.930 to r = 0.995) and approximately linear independently of the test and variable type. Most of the relationship parameters observed from the averaged and maximum force and velocity variable types were strongly related in all tests (r = 0.789-0.991), except for those in vertical jumps (r = 0.485-0.930). However, the generalizability of the force-velocity relationship parameters depicting maximum force, velocity and power of the tested muscles across different tests was inconsistent and on average moderate. We concluded that the linear force-velocity relationship model based on either maximum or averaged force-velocity data could provide the outcomes depicting force, velocity and power generating capacity of the tested muscles, although such outcomes can only be partially generalized across different muscles. PMID:28469742

Does individualism help explain differences in employers' stigmatizing attitudes toward disability across Chinese and American cities?

PubMed

Rao, Deepa; Horton, Randall A; Tsang, Hector W H; Shi, Kan; Corrigan, Patrick W

2010-11-01

Stigmatizing attitudes toward people with disabilities can jeopardize such individuals' well-being and recovery through denial of employment and community isolation. By shaping social norms that define group membership, the construct of individualism may partially explain differences in stigmatizing attitudes across cultures. Further, widespread globalization has brought intensely individualistic social practices to certain segments of non-Western cultures. This paper examines whether the construct of individualism can help to explain cross-cultural differences in stigmatizing attitudes observed between American and Chinese employers. Employers (N = 879) from Beijing, Hong Kong, and Chicago provided information on their attitudes toward hiring people with disabilities, and path analyses were conducted to examine potential mediating relationships. Path analyses indicated that vertical individualism, along with perceived responsibility for acquiring a condition, partially mediated the relationship between culture and employers' negative attitudes about job candidates with disabilities. These results suggested that greater espousal of competitive and individualist values may drive stigmatizing attitudes across cultures. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

Does Individualism Help Explain Differences in Employers' Stigmatizing Attitudes Toward Disability Across Chinese and American Cities?

PubMed Central

Rao, Deepa; Horton, Randall A.; Tsang, Hector W.H.; Shi, Kan; Corrigan, Patrick W.

2011-01-01

Purpose Stigmatizing attitudes toward people with disabilities can jeopardize such individuals' well-being and recovery through denial of employment and community isolation. By shaping social norms that define group membership, the construct of individualism may partially explain differences in stigmatizing attitudes across cultures. Further, widespread globalization has brought intensely individualistic social practices to certain segments of non-Western cultures. This paper examines whether the construct of individualism can help to explain cross-cultural differences in stigmatizing attitudes observed between American and Chinese employers. Design Employers (N = 879) from Beijing, Hong Kong, and Chicago provided information on their attitudes toward hiring people with disabilities, and Path Analyses were conducted to examine potential mediating relationships. Results Path analyses indicated that vertical individualism, along with perceived responsibility for acquiring a condition, partially mediated the relationship between culture and employers' negative attitudes about job candidates with disabilities. Conclusion These results suggested that greater espousal of competitive and individualist values may drive stigmatizing attitudes across cultures. PMID:21171794

Elevated outcome-anticipation and outcome-evaluation ERPs associated with a greater preference for larger-but-delayed rewards.

PubMed

Pornpattananangkul, Narun; Nadig, Ajay; Heidinger, Storm; Walden, Keegan; Nusslock, Robin

2017-06-01

Although waiting for a reward reduces or discounts its value, some people have a stronger tendency to wait for larger rewards and forgo smaller-but-immediate rewards. This ability to delay gratification is captured by individual differences in so-called intertemporal choices in which individuals are asked to choose between larger-but-delayed versus smaller-but-immediate rewards. The current study used event-related potentials (ERPs) to examine whether enhancement in two neurocognitive processes, outcome anticipation and outcome evaluation, modulate individual variability in intertemporal responses. After completing a behavioral intertemporal choice task, 34 participants performed an ERP gambling task. From this ERP task, we separately examined individual differences in outcome anticipation (stimulus-preceding negativity; SPN), early outcome valuation (feedback-related negativity; FRN), and late outcome evaluation (P3). We observed that both elevated outcome-anticipation (SPN) and late outcome-evaluation (P3) neural processes predicted a stronger preference toward larger-but-delayed rewards. No relationship was observed between intertemporal responses and early outcome evaluation (FRN), indicating that the relationship between outcome evaluation and intertemporal responses was specific to the late outcome-evaluation processing stream. Moreover, multiple regression analyses indicated that the SPN and P3 independently modulate individual differences in intertemporal responses, suggesting separate mechanisms underlie the relationship between these two neurocognitive processes and intertemporal responses. Accordingly, we identify two potential neurocognitive modulators of individual variability in intertemporal responses. We discuss the mechanisms underlying these modulators in terms of anticipation-related processing (SPN) and a saliency bias toward gain (compared to loss) outcomes (P3).

Decoding emotion of the other differs among schizophrenia patients and schizoaffective patients: A pilot study.

PubMed

Tadmor, Hagar; Levin, Maya; Dadon, Tzameret; Meiman, Meital E; Ajameeh, Alaa; Mazzawi, Hosam; Rigbi, Amihai; Kremer, Ilana; Golani, Idit; Shamir, Alon

2016-09-01

The deficit in ability to attribute mental states such as thoughts, beliefs, and intentions of another person is a key component in the functional impairment of social cognition in schizophrenia. In the current study, we compared the ability of persons with first episode schizophrenia (FE-SZ) and individuals with schizophrenia displaying symptomatic remission (SZ-CR) to decode the mental state of others with healthy individuals and schizoaffective patients. In addition, we analyzed the effect of dopamine-related genes polymorphism on the ability to decode the mental state of another, and searched for different genetic signatures. Our results show that overall, individuals with schizophrenia performed worse in the "Reading the Mind in the Eyes" (eyes) test, a simple well-defined task to infer the mental state of others than healthy individuals. Within the schizophrenia group, schizoaffective scored significantly higher than FE-SZ, SZ-CR, and healthy individuals. No difference was observed in performance between FE-SZ and SZ-CR subjects. Interestingly, FE-SZ and SZ-CR, but not schizoaffective individuals, performed worse in decoding negative and neutral emotional valance than the healthy control group. At the genetic level, we observed a significant effect of the DAT genotype, but not D4R genotype, on the eyes test performance. Our data suggest that understanding the mental state of another person is a trait marker of the illness, and might serve as an intermediate phenotype in the diagnostic process of schizophrenia disorders, and raise the possibility that DA-related DAT gene might have a role in decoding the mental state of another person.

Effects of mobile phone exposure (GSM 900 and WCDMA/UMTS) on polysomnography based sleep quality: An intra- and inter-individual perspective.

PubMed

Danker-Hopfe, Heidi; Dorn, Hans; Bolz, Thomas; Peter, Anita; Hansen, Marie-Luise; Eggert, Torsten; Sauter, Cornelia

2016-02-01

Studies on effects of radio frequency-electromagnetic fields (RF-EMF) on the macrostructure of sleep so far yielded inconsistent results. This study investigated whether possible effects of RF-EMF exposure differ between individuals. In a double-blind, randomized, sham-controlled cross-over study possible effects of electromagnetic fields emitted by pulsed Global System for Mobile Communications (GSM) 900 and Wideband Code-Division Multiple Access (WCDMA)/Universal Mobile Telecommunications System (WCDMA/UMTS) devices on sleep were analysed. Thirty healthy young men (range 18-30 years) were exposed three times per exposure condition while their sleep was recorded. Sleep was evaluated according to the American Academy of Sleep Medicine standard and eight basic sleep variables were considered. Data analyses at the individual level indicate that RF-EMF effects are observed in 90% of the individuals and that all sleep variables are affected in at least four subjects. While sleep of participants was affected in various numbers, combinations of sleep variables and in different directions, showing improvements but also deteriorations, the only consistent finding was an increase of stage R sleep under GSM 900MHz exposure (9 of 30 subjects) as well as under WCDMA/UMTS exposure (10 of 30 subjects). The results underline that sleep of individuals can be affected differently. The observations found here may indicate an underlying thermal mechanism of RF-EMF on human REM sleep. Nevertheless, the effect of an increase in stage R sleep in one third of the individuals does not necessarily indicate a disturbance of sleep. Copyright © 2015 Elsevier Inc. All rights reserved.

Swim speed, behavior, and movement of North Atlantic right whales (Eubalaena glacialis) in coastal waters of northeastern Florida, USA.

PubMed

Hain, James H W; Hampp, Joy D; McKenney, Sheila A; Albert, Julie A; Kenney, Robert D

2013-01-01

In a portion of the coastal waters of northeastern Florida, North Atlantic right whales (Eubalaena glacialis) occur close to shore from December through March. These waters are included within the designated critical habitat for right whales. Data on swim speed, behavior, and direction of movement--with photo-identification of individual whales--were gathered by a volunteer sighting network working alongside experienced scientists and supplemented by aerial observations. In seven years (2001-2007), 109 tracking periods or "follows" were conducted on right whales during 600 hours of observation from shore-based observers. The whales were categorized as mother-calf pairs, singles and non-mother-calf pairs, and groups of 3 or more individuals. Sample size and amount of information obtained was largest for mother-calf pairs. Swim speeds varied within and across observation periods, individuals, and categories. One category, singles and non mother-calf pairs, was significantly different from the other two--and had the largest variability and the fastest swim speeds. Median swim speed for all categories was 1.3 km/h (0.7 kn), with examples that suggest swim speeds differ between within-habitat movement and migration-mode travel. Within-habitat right whales often travel back-and-forth in a north-south, along-coast, direction, which may cause an individual to pass by a given point on several occasions, potentially increasing anthropogenic risk exposure (e.g., vessel collision, fishing gear entanglement, harassment). At times, mothers and calves engaged in lengthy stationary periods (up to 7.5 h) that included rest, nursing, and play. These mother-calf interactions have implications for communication, learning, and survival. Overall, these behaviors are relevant to population status, distribution, calving success, correlation to environmental parameters, survey efficacy, and human-impacts mitigation. These observations contribute important parameters to conservation biology, predictive modeling, and management. However, while we often search for predictions, patterns, and means, the message here is also about variability and the behavioral characteristics of individual whales.

Population structure and residency patterns of whale sharks, Rhincodon typus, at a provisioning site in Cebu, Philippines.

PubMed

Araujo, Gonzalo; Lucey, Anna; Labaja, Jessica; So, Catherine Lee; Snow, Sally; Ponzo, Alessandro

2014-01-01

This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers' estimated sizes, yielding a good correlation (r (2) = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species' migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity.

Individual Colorimetric Observer Model

PubMed Central

Asano, Yuta; Fairchild, Mark D.; Blondé, Laurent

2016-01-01

This study proposes a vision model for individual colorimetric observers. The proposed model can be beneficial in many color-critical applications such as color grading and soft proofing to assess ranges of color matches instead of a single average match. We extended the CIE 2006 physiological observer by adding eight additional physiological parameters to model individual color-normal observers. These eight parameters control lens pigment density, macular pigment density, optical densities of L-, M-, and S-cone photopigments, and λmax shifts of L-, M-, and S-cone photopigments. By identifying the variability of each physiological parameter, the model can simulate color matching functions among color-normal populations using Monte Carlo simulation. The variabilities of the eight parameters were identified through two steps. In the first step, extensive reviews of past studies were performed for each of the eight physiological parameters. In the second step, the obtained variabilities were scaled to fit a color matching dataset. The model was validated using three different datasets: traditional color matching, applied color matching, and Rayleigh matches. PMID:26862905

Evaluating Music Teachers: A Comparison of Evaluations by Observers with Varied Levels of Musical and Observational Background

ERIC Educational Resources Information Center

Hirokawa, Joy Ondra

2013-01-01

The purpose of this research was to examine the differences in the evaluations of music teachers conducted by individuals with varying backgrounds in music and observation techniques. Part I compared evaluations completed by school administrators and music department leadership. Part II utilized the findings of Part I to create focused and…

Angels and Demons: Using Behavioral Types in a Real-Effort Moral Dilemma to Identify Expert Traits.

PubMed

Bejarano, Hernán D; Green, Ellen P; Rassenti, Stephen J

2016-01-01

In this article, we explore how independently reported measures of subjects' cognitive capabilities, preferences, and sociodemographic characteristics relate to their behavior in a real-effort moral dilemma experiment. To do this, we use a unique dataset, the Chapman Preferences and Characteristics Instrument Set (CPCIS), which contains over 30 standardized measures of preferences and characteristics. We find that simple correlation analysis provides an incomplete picture of how individual measures relate to behavior. In contrast, clustering subjects into groups based on observed behavior in the real-effort task reveals important systematic differences in individual characteristics across groups. However, while we find more differences, these differences are not systematic and difficult to interpret. These results indicate a need for more comprehensive theory explaining how combinations of different individual characteristics impact behavior is needed.

Angels and Demons: Using Behavioral Types in a Real-Effort Moral Dilemma to Identify Expert Traits

PubMed Central

Bejarano, Hernán D.; Green, Ellen P.; Rassenti, Stephen J.

2016-01-01

In this article, we explore how independently reported measures of subjects' cognitive capabilities, preferences, and sociodemographic characteristics relate to their behavior in a real-effort moral dilemma experiment. To do this, we use a unique dataset, the Chapman Preferences and Characteristics Instrument Set (CPCIS), which contains over 30 standardized measures of preferences and characteristics. We find that simple correlation analysis provides an incomplete picture of how individual measures relate to behavior. In contrast, clustering subjects into groups based on observed behavior in the real-effort task reveals important systematic differences in individual characteristics across groups. However, while we find more differences, these differences are not systematic and difficult to interpret. These results indicate a need for more comprehensive theory explaining how combinations of different individual characteristics impact behavior is needed. PMID:27826258

A multilevel study on the association of observer-assessed working conditions with depressive symptoms among female eldercare workers from 56 work units in 10 care homes in Denmark

PubMed Central

Jakobsen, Louise M; Jorgensen, Anette F B; Thomsen, Birthe L; Greiner, Birgit A; Rugulies, Reiner

2015-01-01

Objectives Eldercare workers in Denmark have a higher prevalence of poor psychological health than other occupational groups. We examined the association between working conditions assessed by trained observers and depressive symptoms assessed by self-report in a study of female Danish eldercare workers. Methods Working conditions were observed based on action regulation theory and defined as (1) regulation requirements, a workplace resource providing opportunity for decision-making and skill development and (2) barriers for task completion. We examined the associations of individual and work unit averaged working conditions with depressive symptoms in a sample of 95 individually observed eldercare workers. Further, we examined the association of work unit averaged working conditions with depressive symptoms in a sample of 205 care workers, including both observed and non-observed individuals. We used regression models that allowed for correlations within work units and care homes and adjusted these models for demographics, job characteristics and stressful life events. Results Higher levels of regulation requirements were associated with lower depressive symptoms at the individual level (p=0.04), but not at the workplace level. Barriers were not associated with depressive symptoms at the individual level. At the workplace level, a higher number of qualitatively different barriers (p=0.04) and a higher number of barriers for equipment use (p=0.03) were associated with lower levels of depressive symptoms in the age and cohabitation adjusted model, however statistical significance was lost in the fully adjusted model. Conclusions Low level of regulation requirements was associated with a high level of depressive symptoms. The study highlights the importance of examining both individual and workplace levels of working conditions. PMID:26560058

Sensitivity Analysis of Mixed Models for Incomplete Longitudinal Data

ERIC Educational Resources Information Center

Xu, Shu; Blozis, Shelley A.

2011-01-01

Mixed models are used for the analysis of data measured over time to study population-level change and individual differences in change characteristics. Linear and nonlinear functions may be used to describe a longitudinal response, individuals need not be observed at the same time points, and missing data, assumed to be missing at random (MAR),…

Landscape genetics [Chapter 17

Treesearch

Kevin S. McKelvey; Samuel A. Cushman; Michael K. Schwartz

2009-01-01

In reading this book, you have observed that the spatial data used in landscape ecology come from many sources and in many forms. For many organisms, these data take the form of presence or absence at a location, or numbers of individuals at that same location. For species such as trees, where huge size differences exist between individuals, indices such as basal area...

Torque Teno Midi Virus/Small Anellovirus in Sera of Healthy, HIV/HCV and HIV Infected Individuals in Lorestan Province, Iran

PubMed Central

Fatholahi, Maryam; Bouzari, Majid

2015-01-01

Background: Torque Teno Midi Virus/Small Anellovirus (TTMDV/SAV) is a member of the Gammatorquevirus genus within the family Anelloviridae. It is detected in healthy, Hepatitis B Virus, Hepatitis C Virus and HIV infected individuals and also patients with acute respiratory disease in different countries, but its role in clinical diseases and its full geographical distribution is still unclear. Objectives: The current study aimed to detect the frequency of infection with TTMDV/SAV in the sera of healthy blood donors, hepatitis C infected and HIV positive individuals in Lorestan province, Iran; and also investigate the possible role of TTMDV/SAV virus in liver diseases. Materials and Methods: Fifty two, 36, 4, and 110 serum samples from HIV positive, patients with HIV/HCV and HIV/HCV/HBV co-infections, and healthy individuals were collected in Khorramabad city, respectively. Nested-polymerase chain reaction was performed using SMAs/SMAr primers to detect TTMDV/SAV DNA. Serum aminotransferases were measured. Results: In the HIV/HCV, HIV/HCV/HBV, HIV, and control cases, 29 (80.5%), 3 (75%), 43 (82.7%), and 16 (14.5%) were positive for DNA of TTMDV/SAV, respectively. In the HIV/HCV infected cases and HIV positive cases the level of Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) were not significantly different in TTMDV/SAV infected and non-infected individuals (P > 0.05). Conclusions: Although significant differences (P < 0.01) were observed in the frequency of TTMDV/SAV between healthy controls and each of the HIV positive and HIV/HCV co-infected individuals, no significant difference was observed between HIV positive and HIV/HCV co-infected cases, which may be due to HIV associated immunodeficiency. This is the first time that TTMDV/SAV is reported in HIV infected individuals worldwide. Interpretation of the high frequency of the virus (82.7%) in HIV cases needs more detailed studies. PMID:26862377

Torque Teno Midi Virus/Small Anellovirus in Sera of Healthy, HIV/HCV and HIV Infected Individuals in Lorestan Province, Iran.

PubMed

Fatholahi, Maryam; Bouzari, Majid

2015-11-01

Torque Teno Midi Virus/Small Anellovirus (TTMDV/SAV) is a member of the Gammatorquevirus genus within the family Anelloviridae. It is detected in healthy, Hepatitis B Virus, Hepatitis C Virus and HIV infected individuals and also patients with acute respiratory disease in different countries, but its role in clinical diseases and its full geographical distribution is still unclear. The current study aimed to detect the frequency of infection with TTMDV/SAV in the sera of healthy blood donors, hepatitis C infected and HIV positive individuals in Lorestan province, Iran; and also investigate the possible role of TTMDV/SAV virus in liver diseases. Fifty two, 36, 4, and 110 serum samples from HIV positive, patients with HIV/HCV and HIV/HCV/HBV co-infections, and healthy individuals were collected in Khorramabad city, respectively. Nested-polymerase chain reaction was performed using SMAs/SMAr primers to detect TTMDV/SAV DNA. Serum aminotransferases were measured. In the HIV/HCV, HIV/HCV/HBV, HIV, and control cases, 29 (80.5%), 3 (75%), 43 (82.7%), and 16 (14.5%) were positive for DNA of TTMDV/SAV, respectively. In the HIV/HCV infected cases and HIV positive cases the level of Alanine aminotransferase (ALT) and Aspartate aminotransferase (AST) were not significantly different in TTMDV/SAV infected and non-infected individuals (P > 0.05). Although significant differences (P < 0.01) were observed in the frequency of TTMDV/SAV between healthy controls and each of the HIV positive and HIV/HCV co-infected individuals, no significant difference was observed between HIV positive and HIV/HCV co-infected cases, which may be due to HIV associated immunodeficiency. This is the first time that TTMDV/SAV is reported in HIV infected individuals worldwide. Interpretation of the high frequency of the virus (82.7%) in HIV cases needs more detailed studies.

Dynamics of adrenal steroids are related to variations in Th1 and Treg populations during Mycobacterium tuberculosis infection in HIV positive persons.

PubMed

Quiroga, Maria Florencia; Angerami, Matias Tomas; Santucci, Natalia; Ameri, Diego; Francos, Jose Luis; Wallach, Jorge; Sued, Omar; Cahn, Pedro; Salomón, Horacio; Bottasso, Oscar

2012-01-01

Tuberculosis (TB) remains the most frequent cause of illness and death from an infectious agent, and its interaction with HIV has devastating effects. We determined plasma levels of dehydroepiandrosterone (DHEA), its circulating form DHEA-suphate (DHEA-s) and cortisol in different stages of M. tuberculosis infection, and explored their role on the Th1 and Treg populations during different scenarios of HIV-TB coinfection, including the immune reconstitution inflammatory syndrome (IRIS), a condition related to antiretroviral treatment. DHEA levels were diminished in HIV-TB and HIV-TB IRIS patients compared to healthy donors (HD), HIV+ individuals and HIV+ individuals with latent TB (HIV-LTB), whereas dehydroepiandrosterone sulfate (DHEA-s) levels were markedly diminished in HIV-TB IRIS individuals. HIV-TB and IRIS patients presented a cortisol/DHEA ratio significantly higher than HIV+, HIV-LTB and HD individuals. A positive correlation was observed between DHEA-s and CD4 count among HIV-TB individuals. Conversely, cortisol plasma level inversely correlated with CD4 count within HIV-TB individuals. M. tuberculosis-specific Th1 lymphocyte count was increased after culturing PBMC from HIV-TB individuals in presence of DHEA. We observed an inverse correlation between DHEA-s plasma level and Treg frequency in co-infected individuals, and CD4+FoxP3+ Treg frequency was increased in HIV-TB and IRIS patients compared to other groups. Strikingly, we observed a prominent CD4+CD25-FoxP3+ population across HIV-TB and HIV-TB IRIS patients, which frequency correlated with DHEA plasma level. Finally, DHEA treatment negatively regulated FoxP3 expression without altering Treg frequency in co-infected patients. These data suggest an enhancing role for DHEA in the immune response against M. tuberculosis during HIV-TB coinfection and IRIS.

Dynamics of Adrenal Steroids Are Related to Variations in Th1 and Treg Populations during Mycobacterium tuberculosis Infection in HIV Positive Persons

PubMed Central

Quiroga, Maria Florencia; Angerami, Matias Tomas; Santucci, Natalia; Ameri, Diego; Francos, Jose Luis; Wallach, Jorge; Sued, Omar; Cahn, Pedro; Salomón, Horacio; Bottasso, Oscar

2012-01-01

Tuberculosis (TB) remains the most frequent cause of illness and death from an infectious agent, and its interaction with HIV has devastating effects. We determined plasma levels of dehydroepiandrosterone (DHEA), its circulating form DHEA-suphate (DHEA-s) and cortisol in different stages of M. tuberculosis infection, and explored their role on the Th1 and Treg populations during different scenarios of HIV-TB coinfection, including the immune reconstitution inflammatory syndrome (IRIS), a condition related to antiretroviral treatment. DHEA levels were diminished in HIV-TB and HIV-TB IRIS patients compared to healthy donors (HD), HIV+ individuals and HIV+ individuals with latent TB (HIV-LTB), whereas dehydroepiandrosterone sulfate (DHEA-s) levels were markedly diminished in HIV-TB IRIS individuals. HIV-TB and IRIS patients presented a cortisol/DHEA ratio significantly higher than HIV+, HIV-LTB and HD individuals. A positive correlation was observed between DHEA-s and CD4 count among HIV-TB individuals. Conversely, cortisol plasma level inversely correlated with CD4 count within HIV-TB individuals. M. tuberculosis-specific Th1 lymphocyte count was increased after culturing PBMC from HIV-TB individuals in presence of DHEA. We observed an inverse correlation between DHEA-s plasma level and Treg frequency in co-infected individuals, and CD4+FoxP3+ Treg frequency was increased in HIV-TB and IRIS patients compared to other groups. Strikingly, we observed a prominent CD4+CD25-FoxP3+ population across HIV-TB and HIV-TB IRIS patients, which frequency correlated with DHEA plasma level. Finally, DHEA treatment negatively regulated FoxP3 expression without altering Treg frequency in co-infected patients. These data suggest an enhancing role for DHEA in the immune response against M. tuberculosis during HIV-TB coinfection and IRIS. PMID:22431997

Spectrotemporal dynamics of the EEG during working memory encoding and maintenance predicts individual behavioral capacity.

PubMed

Bashivan, Pouya; Bidelman, Gavin M; Yeasin, Mohammed

2014-12-01

We investigated the effect of memory load on encoding and maintenance of information in working memory. Electroencephalography (EEG) signals were recorded while participants performed a modified Sternberg visual memory task. Independent component analysis (ICA) was used to factorise the EEG signals into distinct temporal activations to perform spectrotemporal analysis and localisation of source activities. We found 'encoding' and 'maintenance' operations were correlated with negative and positive changes in α-band power, respectively. Transient activities were observed during encoding of information in the bilateral cuneus, precuneus, inferior parietal gyrus and fusiform gyrus, and a sustained activity in the inferior frontal gyrus. Strong correlations were also observed between changes in α-power and behavioral performance during both encoding and maintenance. Furthermore, it was also found that individuals with higher working memory capacity experienced stronger neural oscillatory responses during the encoding of visual objects into working memory. Our results suggest an interplay between two distinct neural pathways and different spatiotemporal operations during the encoding and maintenance of information which predict individual differences in working memory capacity observed at the behavioral level. © 2014 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Temperament in rhesus, long-tailed, and pigtailed macaques varies by species and sex

PubMed Central

Sussman, Adrienne F.; Ha, James C.; Bentson, Kathy L.; Crockett, Carolyn M.

2012-01-01

Temperament differs among individuals both within and between species. Evidence suggests that differences in temperament of group members may parallel differences in social behavior among groups or between species. Here, we compared temperament between three closely related species of monkey - rhesus (Macaca mulatta), long-tailed (M. fascicularis), and pigtailed (M. nemestrina) macaques - using cage-front behavioral observations of individually housed monkeys at a National Primate Research Center. Frequencies of 12 behaviors in 899 subjects were analyzed using a PCA to identify temperament components. The analysis identified four components, which we interpreted as Sociability towards humans, Cautiousness, Aggressiveness, and Fearfulness. Species and sexes differed in their average scores on these components, even after controlling for differences in age and early-life experiences. Our results suggest that rhesus macaques are especially aggressive and unsociable towards humans, long-tailed macaques are more cautious and fearful, and pigtailed macaques are more sociable towards humans and less aggressive than the other species. Pigtailed males were notably more sociable than any other group. The differences observed are consistent with reported variation in these species’ social behaviors, as rhesus macaques generally engage in more social aggression and pigtailed macaques engage in more male-male affiliative behaviors. Differences in predation risks are among the socioecological factors that might make these species-typical behaviors adaptive. Our results suggest that adaptive species-level social differences may be encoded in individual-level temperaments, which are manifested even outside of a social context. PMID:23225368

Testing Models for the Contributions of Genes and Environment to Developmental Change in Adolescent Depression

PubMed Central

Eaves, Lindon J.; Maes, Hermine; Silberg, Judy L.

2015-01-01

We tested two models to identify the genetic and environmental processes underlying longitudinal changes in depression among adolescents. The first assumes that observed changes in covariance structure result from the unfolding of inherent, random individual differences in the overall levels and rates of change in depression over time (random growth curves). The second assumes that observed changes are due to time-specific random effects (innovations) accumulating over time (autoregressive effects). We found little evidence of age-specific genetic effects or persistent genetic innovations. Instead, genetic effects are consistent with a gradual unfolding in the liability to depression and rates of change with increasing age. Likewise, the environment also creates significant individual differences in overall levels of depression and rates of change. However, there are also time-specific environmental experiences that persist with fidelity. The implications of these differing genetic and environmental mechanisms in the etiology of depression are considered. PMID:25894924

Testing Models for the Contributions of Genes and Environment to Developmental Change in Adolescent Depression.

PubMed

Gillespie, Nathan A; Eaves, Lindon J; Maes, Hermine; Silberg, Judy L

2015-07-01

We tested two models to identify the genetic and environmental processes underlying longitudinal changes in depression among adolescents. The first assumes that observed changes in covariance structure result from the unfolding of inherent, random individual differences in the overall levels and rates of change in depression over time (random growth curves). The second assumes that observed changes are due to time-specific random effects (innovations) accumulating over time (autoregressive effects). We found little evidence of age-specific genetic effects or persistent genetic innovations. Instead, genetic effects are consistent with a gradual unfolding in the liability to depression and rates of change with increasing age. Likewise, the environment also creates significant individual differences in overall levels of depression and rates of change. However, there are also time-specific environmental experiences that persist with fidelity. The implications of these differing genetic and environmental mechanisms in the etiology of depression are considered.

Glucose 6-phosphate dehydrogenase: isoenzymatic pattern in Oesophagostomum venulosum, Trichuris ovis and T. suis.

PubMed

Rodriguez, B; Cutillas, C; German, P; Guevara, D

1991-12-01

In the present communication we have studied the isoenzymatic pattern activity of the glucose 6-phosphate dehydrogenase (G6PD) in Oesophagostomum venulosum, Trichuris ovis and T. suis, parasites of Capra hircus (goat), Ovis aries (sheep) and Sus scrofa domestica (pig) respectively, by polyacrylamide gel electrophoresis. Different phenotypes have been observed in the G6PD isoenzymatic pattern activity in males and females of Oesophagostomum venulosum. Furthermore, G6PD activity has been assayed in Trichuris ovis collected from Ovis aries and Capra hircus. No differences have been observed in the isoenzymatic patterns attending to the different hosts. All the individuals exhibited one single band or two bands; this suggests a monomeric condition for G6PD in T. ovis. In T. suis the enzyme G6PD appeared as a single electrophoretic band in about 85.7% of the individuals.

Observed differences in learning ability of heart rate self-regulation as a function of hypnotic susceptibility

NASA Technical Reports Server (NTRS)

Cowings, P. S.

1977-01-01

Three groups of eight male and female subjects (aged 20-27 yr) categorized by low and high hypnotic susceptibility were taught to control their heart rates by means of an appropriate autogenic therapy/biofeedback technique. The experimental groups were trained by autogenic therapy and biofeedback, while the control group received only biofeedback. Significant differences are observed in all psychological test scores between subjects of high and low hypnotic susceptibility. The results confirm that (1) there are qualitative and quantitative differences between the performance of individuals with high and low hypnotic susceptibility; (2) interindividual-variability tests yield data relevant to individual performance in visceral learning tasks; (3) the combined autogenic therapy/biofeedback/verbal feedback technique is suitable for conditioning large stable autonomic responses in humans; and (4) this kind of conditioning is effective in eliminating or alleviating physiological reactions to some environmental stressors.

Uncertainty assessment and implications for data acquisition in support of integrated hydrologic models

NASA Astrophysics Data System (ADS)

Brunner, Philip; Doherty, J.; Simmons, Craig T.

2012-07-01

The data set used for calibration of regional numerical models which simulate groundwater flow and vadose zone processes is often dominated by head observations. It is to be expected therefore, that parameters describing vadose zone processes are poorly constrained. A number of studies on small spatial scales explored how additional data types used in calibration constrain vadose zone parameters or reduce predictive uncertainty. However, available studies focused on subsets of observation types and did not jointly account for different measurement accuracies or different hydrologic conditions. In this study, parameter identifiability and predictive uncertainty are quantified in simulation of a 1-D vadose zone soil system driven by infiltration, evaporation and transpiration. The worth of different types of observation data (employed individually, in combination, and with different measurement accuracies) is evaluated by using a linear methodology and a nonlinear Pareto-based methodology under different hydrological conditions. Our main conclusions are (1) Linear analysis provides valuable information on comparative parameter and predictive uncertainty reduction accrued through acquisition of different data types. Its use can be supplemented by nonlinear methods. (2) Measurements of water table elevation can support future water table predictions, even if such measurements inform the individual parameters of vadose zone models to only a small degree. (3) The benefits of including ET and soil moisture observations in the calibration data set are heavily dependent on depth to groundwater. (4) Measurements of groundwater levels, measurements of vadose ET or soil moisture poorly constrain regional groundwater system forcing functions.

Bayes and empirical Bayes estimators of abundance and density from spatial capture-recapture data

USGS Publications Warehouse

Dorazio, Robert M.

2013-01-01

In capture-recapture and mark-resight surveys, movements of individuals both within and between sampling periods can alter the susceptibility of individuals to detection over the region of sampling. In these circumstances spatially explicit capture-recapture (SECR) models, which incorporate the observed locations of individuals, allow population density and abundance to be estimated while accounting for differences in detectability of individuals. In this paper I propose two Bayesian SECR models, one for the analysis of recaptures observed in trapping arrays and another for the analysis of recaptures observed in area searches. In formulating these models I used distinct submodels to specify the distribution of individual home-range centers and the observable recaptures associated with these individuals. This separation of ecological and observational processes allowed me to derive a formal connection between Bayes and empirical Bayes estimators of population abundance that has not been established previously. I showed that this connection applies to every Poisson point-process model of SECR data and provides theoretical support for a previously proposed estimator of abundance based on recaptures in trapping arrays. To illustrate results of both classical and Bayesian methods of analysis, I compared Bayes and empirical Bayes esimates of abundance and density using recaptures from simulated and real populations of animals. Real populations included two iconic datasets: recaptures of tigers detected in camera-trap surveys and recaptures of lizards detected in area-search surveys. In the datasets I analyzed, classical and Bayesian methods provided similar – and often identical – inferences, which is not surprising given the sample sizes and the noninformative priors used in the analyses.

Bayes and empirical Bayes estimators of abundance and density from spatial capture-recapture data.

PubMed

Dorazio, Robert M

2013-01-01

In capture-recapture and mark-resight surveys, movements of individuals both within and between sampling periods can alter the susceptibility of individuals to detection over the region of sampling. In these circumstances spatially explicit capture-recapture (SECR) models, which incorporate the observed locations of individuals, allow population density and abundance to be estimated while accounting for differences in detectability of individuals. In this paper I propose two Bayesian SECR models, one for the analysis of recaptures observed in trapping arrays and another for the analysis of recaptures observed in area searches. In formulating these models I used distinct submodels to specify the distribution of individual home-range centers and the observable recaptures associated with these individuals. This separation of ecological and observational processes allowed me to derive a formal connection between Bayes and empirical Bayes estimators of population abundance that has not been established previously. I showed that this connection applies to every Poisson point-process model of SECR data and provides theoretical support for a previously proposed estimator of abundance based on recaptures in trapping arrays. To illustrate results of both classical and Bayesian methods of analysis, I compared Bayes and empirical Bayes esimates of abundance and density using recaptures from simulated and real populations of animals. Real populations included two iconic datasets: recaptures of tigers detected in camera-trap surveys and recaptures of lizards detected in area-search surveys. In the datasets I analyzed, classical and Bayesian methods provided similar - and often identical - inferences, which is not surprising given the sample sizes and the noninformative priors used in the analyses.

Can we infer post mortem interval on the basis of decomposition rate? A case from a Portuguese cemetery.

PubMed

Ferreira, M Teresa; Cunha, Eugénia

2013-03-10

Post mortem interval estimation is crucial in forensic sciences for both positive identification and reconstruction of perimortem events. However, reliable dating of skeletonized remains poses a scientific challenge since human remains decomposition involves a set of complex and highly variable processes. Many of the difficulties in determining post mortem interval and/or the permanence of a body in a specific environment relates with the lack of systematic observations and research in human body decomposition modalities in different environments. In March 2006, in order to solve a problem of misidentification, a team of the South Branch of Portuguese National Institute of Legal Medicine carried out the exhumation of 25 identified individuals buried for almost five years in the same cemetery plot. Even though all individuals shared similar post mortem intervals, they presented different stages of decomposition. In order to analyze the post mortem factors associated with the different stages of decomposition displayed by the 25 exhumed individuals, the stages of decomposition were scored. Information regarding age at death and sex of the individuals were gathered and recorded as well as data in the cause of death and grave and coffin characteristics. Although the observed distinct decay stages may be explained by the burial conditions, namely by the micro taphonomic environments, individual endogenous factors also play an important role on differential decomposition as witnessed by the present case. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Prevalence, distribution of serotypes, and cariogenic potential in hamsters of mutans streptococci from elderly individuals.

PubMed

Fitzgerald, D B; Fitzgerald, R J; Adams, B O; Morhart, R E

1983-08-01

The prevalence of mutans streptococci (Streptococcus mutans, Streptococcus cricetus, Streptococcus sobrinus, and Streptococcus rattus) was determined in the salivas of 169 elderly individuals ranging in age from 60 to 87 years. Approximately 40% of these individuals were edentulous and wore full upper and lower dentures. With the exception of a higher proportion of saliva counts below 1,000 CFU/ml in the full-denture wearers, the prevalence and the serotype and species distributions of the mutans streptococci were similar in the denture wearers and individuals with natural teeth only. The species and serotype distributions of mutans streptococci in this elderly population were also consistent with reported observations of other workers on younger, more caries-prone populations. A total of 87 representative isolates of the mutans streptococci were tested for cariogenic potential in a hamster model system. A considerable degree of variation in virulence between different strains was observed. However, these differences were not relatable to individual species or serotypes or to whether the organisms were isolated from denture wearers or naturally dentate subjects. The results of our studies indicate that elderly individuals with either natural or artificial dentitions may be a hitherto unrecognized reservoir of mutans streptococci having varying degrees of potential cariogenicity. Hence, in close family situations they could serve, along with parents and siblings, as vectors in the initial transmission of cariogenic microorganisms to young children.

Neural mechanisms and personality correlates of the sunk cost effect

PubMed Central

Fujino, Junya; Fujimoto, Shinsuke; Kodaka, Fumitoshi; Camerer, Colin F.; Kawada, Ryosaku; Tsurumi, Kosuke; Tei, Shisei; Isobe, Masanori; Miyata, Jun; Sugihara, Genichi; Yamada, Makiko; Fukuyama, Hidenao; Murai, Toshiya; Takahashi, Hidehiko

2016-01-01

The sunk cost effect, an interesting and well-known maladaptive behavior, is pervasive in real life, and thus has been studied in various disciplines, including economics, psychology, organizational behavior, politics, and biology. However, the neural mechanisms underlying the sunk cost effect have not been clearly established, nor have their association with differences in individual susceptibility to the effect. Using functional magnetic resonance imaging, we investigated neural responses induced by sunk costs along with measures of core human personality. We found that individuals who tend to adhere to social rules and regulations (who are high in measured agreeableness and conscientiousness) are more susceptible to the sunk cost effect. Furthermore, this behavioral observation was strongly mediated by insula activity during sunk cost decision-making. Tight coupling between the insula and lateral prefrontal cortex was also observed during decision-making under sunk costs. Our findings reveal how individual differences can affect decision-making under sunk costs, thereby contributing to a better understanding of the psychological and neural mechanisms of the sunk cost effect. PMID:27611212

Activity level in the lab: Overlap with shyness indicates it is more than pure motoric activity

USDA-ARS?s Scientific Manuscript database

The observation that children's activity level (AL) differs between novel and familiar situations is well established. What influences individual differences in how AL is different across these situations is less well understood. Drawing on animal literature, which links rats' AL when 1st placed in ...

Analyzing for Individual Differences in Evaluating Compensatory Education Programs. Occasional Paper No. 27.

ERIC Educational Resources Information Center

Krus, Patricia H.

Trait-Treatment Interaction (TTI), a research method for observing experimental effects of treatments on subjects of different aptitudes and learning characteristics, is suggested as an effective evaluation tool to provide evaluators and educators in compensatory education programs with information about which program is best for different kinds…

Sex Differences in Brain Activity Related to General and Emotional Intelligence

ERIC Educational Resources Information Center

Jausovec, Norbert; Jausovec, Ksenija

2005-01-01

The study investigated gender differences in resting EEG (in three individually determined narrow [alpha] frequency bands) related to the level of general and emotional intelligence. Brain activity of males decreased with the level of general intelligence, whereas an opposite pattern of brain activity was observed in females. This difference was…

Pulp and paper mill effluent treatments have differential endocrine-disrupting effects on rainbow trout.

PubMed

Orrego, Rodrigo; Guchardi, John; Hernandez, Victor; Krause, Rachelle; Roti, Lucia; Armour, Jeffrey; Ganeshakumar, Mathumai; Holdway, Douglas

2009-01-01

Endocrine disruption (ED) effects due to pulp and paper mill effluents extracts involving different industrial procedures and effluent treatments (nontreated, primary, and secondary treated) were evaluated using immature triploid rainbow trout in a pulse-exposure toxicity experiment. The protocol involved the use of intraperitoneal injection of mill extracts (solid-phase extraction [SPE]) corrected for individual fish weight and included several laboratory standards (steroidal hormones and phytosterols). Biological endpoints at two different levels of biological organization were analyzed (molecular and individual organism). Results indicated that nonsignificant changes were observed in the individual physiological indices represented by condition factor, liver somatic index, and gonad somatic index during the experiment. Significant induction of liver ethoxyresorufin-O-deethylase activity was observed between different effluent treatments and experimental controls. Significant endocrine-disrupting effects at the reproductive level were observed in all effluent treatments involving significant increments in plasma vitellogenin (VTG) levels. Fish exposed to untreated effluent extracts had significantly higher VTG levels compared to fish exposed to primary and secondary treatment effluent extracts, indicating a decrease of the estrogenic effect due to the effluent treatment. The present study has shown that for the Chilean pulp and paper mill SPE extracts evaluated, an endocrine disruption effect was induced in immature triploid rainbow, reaffirming the significant estrogenic effects demonstrated previously in laboratory and field experiments.

Can the Discrepancy between Locally and Globally Derived Neutral Hydrogen Mass Functions be Explained by a Varying Value of M ⋆?

NASA Astrophysics Data System (ADS)

Minchin, Robert F.

2017-09-01

I investigate whether it is possible to reconcile the recent Arecibo Legacy Fast Arecibo L-band Feed Array (ALFALFA) observation that the neutral hydrogen mass function (HIMF) across different galactic densities has the same, non-flat, faint-end slope, with observations of isolated galaxies and many galaxy groups that show their HIMFs to have flat faint-end slopes. I find that a fairly simple model in which the position of the knee in the mass function of each individual group is allowed to vary is able to account for both of these observations. If this model reflects reality, the ALFALFA results point to an interesting “conspiracy” whereby the differing group HIMFs always sum up to form global HIMFs with the same faint-end slope in different environments. More generally, this result implies that global environmental HIMFs do not necessarily reflect the HIMFs in individual groups belonging to that environment and cannot be used to directly measure variations in group-specific HIMFs with environment.

Physiological and behavioral effects of tilt-induced body fluid shifts

NASA Technical Reports Server (NTRS)

Parker, D. E.; Tjernstrom, O.; Ivarsson, A.; Gulledge, W. L.; Poston, R. L.

1983-01-01

This paper addresses the 'fluid shift theory' of space motion sickness. The primary purpose of the research was the development of procedures to assess individual differences in response to rostral body fluid shifts on earth. Experiment I examined inner ear fluid pressure changes during head-down tilt in intact human beings. Tilt produced reliable changes. Differences among subjects and between ears within the same subject were observed. Experiment II examined auditory threshold changes during tilt. Tilt elicited increased auditory thresholds, suggesting that sensory depression may result from increased inner ear fluid pressure. Additional observations on rotation magnitude estimation during head-down tilt, which indicate that rostral fluid shifts may depress semicircular canal activity, are briefly described. The results of this research suggest that the inner ear pressure and auditory threshold shift procedures could be used to assess individual differences among astronauts prior to space flight. Results from the terrestrial observations could be related to reported incidence/severity of motion sickness in space and used to evaluate the fluid shift theory of space motion sickness.

Temporal dynamics of physical activity and affect in depressed and nondepressed individuals.

PubMed

Stavrakakis, Nikolaos; Booij, Sanne H; Roest, Annelieke M; de Jonge, Peter; Oldehinkel, Albertine J; Bos, Elisabeth H

2015-12-01

The association between physical activity and affect found in longitudinal observational studies is generally small to moderate. It is unknown how this association generalizes to individuals. The aim of the present study was to investigate interindividual differences in the bidirectional dynamic relationship between physical activity and affect, in depressed and nondepressed individuals, using time-series analysis. A pair-matched sample of 10 depressed and 10 nondepressed participants (mean age = 36.6, SD = 8.9, 30% males) wore accelerometers and completed electronic questionnaires 3 times a day for 30 days. Physical activity was operationalized as the total energy expenditure (EE) per day segment (i.e., 6 hr). The multivariate time series (T = 90) of every individual were analyzed using vector autoregressive modeling (VAR), with the aim to assess direct as well as lagged (i.e., over 1 day) effects of EE on positive and negative affect, and vice versa. Large interindividual differences in the strength, direction and temporal aspects of the relationship between physical activity and positive and negative affect were observed. An exception was the direct (but not the lagged) effect of physical activity on positive affect, which was positive in nearly all individuals. This study showed that the association between physical activity and affect varied considerably across individuals. Thus, while at the group level the effect of physical activity on affect may be small, in some individuals the effect may be clinically relevant. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

Obese individuals with type 2 diabetes demonstrate decreased activation of the salience-related insula and increased activation of the emotion/salience-related amygdala to visual food cues compared to non-obese individuals with diabetes: a preliminary study.

PubMed

Farr, Olivia M; Mantzoros, Christos S

2018-06-08

A better understanding of the underlying pathophysiology of obesity and its comorbidities is needed to develop more effective therapeutics. Although several studies have observed differences in CNS activation/deactivation patterns between obese and lean individuals when viewing food cues, few studies have examined whether the same holds true among diabetics. We examined cross-sectionally, using functional magnetic resonance imaging (fMRI), differences in brain activation to food cues between obese (n=6) vs. non-obese (n=5) individuals with type 2 diabetes. Obese individuals with type 2 diabetes demonstrate less activation of the salience- and reward-related insula while fasting and increased activation of the amygdala to highly desirable foods after a meal. Our findings in type 2 diabetes suggest a persistence of differences between obese versus non-obese individuals. Future, larger studies should confirm this differential activation between lean and obese individuals with and without type 2 diabetes. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Gender differences in reward and punishment for monetary and social feedback in children: An ERP study

PubMed Central

Zou, Yuchen; Song, Yan; Xiao, Xue; Huang, Wanyi; Li, Yanfang

2017-01-01

Gender differences in feedback processing have been observed among adolescents and adults through event-related potentials. However, information on whether and how this feedback processing is affected by feedback valence, feedback type, and individual sensitivity in reward/punishment among children remains minimal. In this study, we used a guessing game task coupled with electroencephalography to investigate gender differences in feedback processing, in which feedback to reward and punishment was presented in the context of monetary and social conditions. Results showed that boys were less likely to switch their response after punishment, had generally less feedback-related negativity (FRN) amplitude, and longer FRN latency in monetary and punishment conditions than girls. Moreover, FRN for monetary punishment, which is related to individual difference in reward sensitivity, was observed only in girls. The study provides gender-specific evidence for the neural processing of feedback, which may offer educational guidance for appropriate feedback for girls and boys. PMID:28346515

Intrapersonal characteristics of body-related guilt, shame, pride, and envy in Canadian adults.

PubMed

Pila, Eva; Brunet, Jennifer; Crocker, Peter R E; Kowalski, Kent C; Sabiston, Catherine M

2016-03-01

This study examined differences in body-related shame, guilt, pride, and envy based on intrapersonal characteristics of sex, age, and weight status in 527 Canadian adults. Compared to men, women reported significantly higher shame and guilt contextualized to the body. No sex differences were observed for envy or pride. Middle-aged adults reported higher shame and lower pride compared with young adults, whereas no age differences were observed with body-related guilt. Meanwhile, shame and guilt were highest for individuals who had overweight or obese weight status, and pride was highest in individuals with average weight status. Overall, effect sizes were small and there were no significant interaction effects between sex, age, and weight status across body-related emotions. Further research is needed to capture similarities and differences of body-related self-conscious emotions between intrapersonal characteristics, to aid the development of intervention strategies to manage this important dimension of body image. Copyright © 2016 Elsevier Ltd. All rights reserved.

Logical-rules and the classification of integral dimensions: individual differences in the processing of arbitrary dimensions

PubMed Central

Blunden, Anthea G.; Wang, Tony; Griffiths, David W.; Little, Daniel R.

2015-01-01

A variety of converging operations demonstrate key differences between separable dimensions, which can be analyzed independently, and integral dimensions, which are processed in a non-analytic fashion. A recent investigation of response time distributions, applying a set of logical rule-based models, demonstrated that integral dimensions are pooled into a single coactive processing channel, in contrast to separable dimensions, which are processed in multiple, independent processing channels. This paper examines the claim that arbitrary dimensions created by factorially morphing four faces are processed in an integral manner. In two experiments, 16 participants completed a categorization task in which either upright or inverted morph stimuli were classified in a speeded fashion. Analyses focused on contrasting different assumptions about the psychological representation of the stimuli, perceptual and decisional separability, and the processing architecture. We report consistent individual differences which demonstrate a mixture of some observers who demonstrate coactive processing with other observers who process the dimensions in a parallel self-terminating manner. PMID:25620941

Gender differences in reward and punishment for monetary and social feedback in children: An ERP study.

PubMed

Ding, Ying; Wang, Encong; Zou, Yuchen; Song, Yan; Xiao, Xue; Huang, Wanyi; Li, Yanfang

2017-01-01

Gender differences in feedback processing have been observed among adolescents and adults through event-related potentials. However, information on whether and how this feedback processing is affected by feedback valence, feedback type, and individual sensitivity in reward/punishment among children remains minimal. In this study, we used a guessing game task coupled with electroencephalography to investigate gender differences in feedback processing, in which feedback to reward and punishment was presented in the context of monetary and social conditions. Results showed that boys were less likely to switch their response after punishment, had generally less feedback-related negativity (FRN) amplitude, and longer FRN latency in monetary and punishment conditions than girls. Moreover, FRN for monetary punishment, which is related to individual difference in reward sensitivity, was observed only in girls. The study provides gender-specific evidence for the neural processing of feedback, which may offer educational guidance for appropriate feedback for girls and boys.

Fragmentation, Fusion, and Genetic Homogeneity in a Calcareous Sponge (Porifera, Calcarea).

PubMed

Padua, André; Leocorny, Pedro; Custódio, Márcio Reis; Klautau, Michelle

2016-06-01

Sessile marine invertebrates living on hard substrata usually present strategies such as size variations, longer life spans, fragmentation and fusion to occupy and compete for space. Calcareous sponges are usually small and short-lived, and some species are known to undergo frequent fragmentation and fusion events. However, whether fusion occurs only between genetically identical individuals remains unclear. We investigated the occurrence of chimaeras in the calcareous sponge Clathrina aurea by following the dynamics of fragmentation and fusion of 66 individuals in the field for up to 18 months and determined size variations and the life span of each individual. Microsatellites were used to determine whether fusion events occur among genetically different individuals. Growth and shrinkage of individuals were frequently observed, showing that size cannot be associated with age in C. aurea. The life span of the species ranged from 1 to 16 months (mean: 4.7 months). Short life spans and variable growth rates have been observed in other species of the class Calcarea. Fragmentation and fusion events were observed, but fusion events always occurred between genetically identical individuals, as has been suggested by graft experiments in adult Demospongiae and other Calcarea. These results suggest that at least C. aurea adults may have some mechanism to avoid chimaerism. © 2016 Wiley Periodicals, Inc.

Predicting functional divergence in protein evolution by site-specific rate shifts

NASA Technical Reports Server (NTRS)

Gaucher, Eric A.; Gu, Xun; Miyamoto, Michael M.; Benner, Steven A.

2002-01-01

Most modern tools that analyze protein evolution allow individual sites to mutate at constant rates over the history of the protein family. However, Walter Fitch observed in the 1970s that, if a protein changes its function, the mutability of individual sites might also change. This observation is captured in the "non-homogeneous gamma model", which extracts functional information from gene families by examining the different rates at which individual sites evolve. This model has recently been coupled with structural and molecular biology to identify sites that are likely to be involved in changing function within the gene family. Applying this to multiple gene families highlights the widespread divergence of functional behavior among proteins to generate paralogs and orthologs.

Risk, individual differences, and environment: an Agent-Based Modeling approach to sexual risk-taking.

PubMed

Nagoski, Emily; Janssen, Erick; Lohrmann, David; Nichols, Eric

2012-08-01

Risky sexual behaviors, including the decision to have unprotected sex, result from interactions between individuals and their environment. The current study explored the use of Agent-Based Modeling (ABM)-a methodological approach in which computer-generated artificial societies simulate human sexual networks-to assess the influence of heterogeneity of sexual motivation on the risk of contracting HIV. The models successfully simulated some characteristics of human sexual systems, such as the relationship between individual differences in sexual motivation (sexual excitation and inhibition) and sexual risk, but failed to reproduce the scale-free distribution of number of partners observed in the real world. ABM has the potential to inform intervention strategies that target the interaction between an individual and his or her social environment.

Comparison of Efficacy and Safety of Liraglutide 3.0 mg in Individuals with BMI above and below 35 kg/m²: A Post-hoc Analysis.

PubMed

le Roux, Carel; Aroda, Vanita; Hemmingsson, Joanna; Cancino, Ana Paula; Christensen, Rune; Pi-Sunyer, Xavier

2017-01-01

To investigate whether the efficacy and safety of liraglutide 3.0 mg differed between two subgroups, BMI 27 to <35 and BMI ≥ 35 kg/m², in individuals without and with type 2 diabetes (T2D). A post-hoc analysis of two 56-week, randomized, double-blind, placebo-controlled trials (SCALE Obesity and Prediabetes; SCALE Diabetes). Subgroup differences in treatment effects of liraglutide 3.0 mg were evaluated by testing the interaction between treatment group and baseline BMI subgroup. Significantly greater weight loss (0-56 weeks) was observed with liraglutide 3.0 mg versus placebo in all patient groups while on treatment. There was no evidence that the weight-lowering effect of liraglutide 3.0 mg differed between BMI subgroups (interaction p > 0.05). Similarly, for most secondary endpoints significantly greater improvements were observed with liraglutide 3.0 mg versus placebo, with no indication treatment effects differing between subgroups. The safety profile of liraglutide 3.0 mg was broadly similar across BMI subgroups. This post-hoc analysis did not indicate any differences in the treatment effects, or safety profile, of liraglutide 3.0 mg for individuals with BMI 27 to <35 or ≥35 kg/m². Liraglutide 3.0 mg can therefore be considered for individuals with a BMI of ≥35 as well as for those with a BMI of 27 to <35 kg/m². © 2017 The Author(s) Published by S. Karger GmbH, Freiburg.

Individual differences in the forced swimming test and neurochemical kinetics in the rat brain.

PubMed

Sequeira-Cordero, Andrey; Mora-Gallegos, Andrea; Cuenca-Berger, Patricia; Fornaguera-Trías, Jaime

2014-04-10

Individual differences in the forced swimming test (FST) could be associated with differential temporal dynamics of gene expression and neurotransmitter activity. We tested juvenile male rats in the FST and classified the animals into those with low and high immobility according to the amount of immobility time recorded in FST. These groups and a control group which did not undergo the FST were sacrificed either 1, 6 or 24 h after the test. We analyzed the expression of the CRF, CRFR1, BDNF and TrkB in the prefrontal cortex, hippocampus and nucleus accumbens as well as norepinephrine, dopamine, serotonin, glutamate, GABA and glutamine in the hippocampus and nucleus accumbens. Animals with low immobility showed significant reductions of BDNF expression across time points in both the prefrontal cortex and the nucleus accumbens when compared with non-swim control. Moreover, rats with high immobility only showed a significant decrease of BDNF expression in the prefrontal cortex 6h after the FST. Regarding neurotransmitters, only accumbal dopamine turnover and hippocampal glutamate content showed an effect of individual differences (i.e. animals with low and high immobility), whereas nearly all parameters showed significant differences across time points. Correlational analyses suggest that immobility in the FST, probably reflecting despair, is related to prefrontal cortical BDNF and to the kinetics observed in several other neurochemical parameters. Taken together, our results suggest that individual differences observed in depression-like behavior can be associated not only with changes in the concentrations of key neurochemical factors but also with differential time courses of such factors. Copyright © 2014 Elsevier Inc. All rights reserved.

Speech Prosody Across Stimulus Types for Individuals with Parkinson's Disease.

PubMed

K-Y Ma, Joan; Schneider, Christine B; Hoffmann, Rüdiger; Storch, Alexander

2015-01-01

Up to 89% of the individuals with Parkinson's disease (PD) experience speech problem over the course of the disease. Speech prosody and intelligibility are two of the most affected areas in hypokinetic dysarthria. However, assessment of these areas could potentially be problematic as speech prosody and intelligibility could be affected by the type of speech materials employed. To comparatively explore the effects of different types of speech stimulus on speech prosody and intelligibility in PD speakers. Speech prosody and intelligibility of two groups of individuals with varying degree of dysarthria resulting from PD was compared to that of a group of control speakers using sentence reading, passage reading and monologue. Acoustic analysis including measures on fundamental frequency (F0), intensity and speech rate was used to form a prosodic profile for each individual. Speech intelligibility was measured for the speakers with dysarthria using direct magnitude estimation. Difference in F0 variability between the speakers with dysarthria and control speakers was only observed in sentence reading task. Difference in the average intensity level was observed for speakers with mild dysarthria to that of the control speakers. Additionally, there were stimulus effect on both intelligibility and prosodic profile. The prosodic profile of PD speakers was different from that of the control speakers in the more structured task, and lower intelligibility was found in less structured task. This highlighted the value of both structured and natural stimulus to evaluate speech production in PD speakers.

Validity of Different Activity Monitors to Count Steps in an Inpatient Rehabilitation Setting.

PubMed

Treacy, Daniel; Hassett, Leanne; Schurr, Karl; Chagpar, Sakina; Paul, Serene S; Sherrington, Catherine

2017-05-01

Commonly used activity monitors have been shown to be accurate in counting steps in active people; however, further validation is needed in slower walking populations. To determine the validity of activity monitors for measuring step counts in rehabilitation inpatients compared with visually observed step counts. To explore the influence of gait parameters, activity monitor position, and use of walkers on activity monitor accuracy. One hundred and sixty-six inpatients admitted to a rehabilitation unit with an average walking speed of 0.4 m/s (SD 0.2) wore 16 activity monitors (7 different devices in different positions) simultaneously during 6-minute and 6-m walks. The number of steps taken during the tests was also counted by a physical therapist. Gait parameters were assessed using the GAITRite system. To analyze the influence of different gait parameters, the percentage accuracy for each monitor was graphed against various gait parameters for each activity monitor. The StepWatch, Fitbit One worn on the ankle and the ActivPAL showed excellent agreement with observed step count (ICC 2,1 0.98; 0.92; 0.78 respectively). Other devices (Fitbit Charge, Fitbit One worn on hip, G-Sensor, Garmin Vivofit, Actigraph) showed poor agreement with the observed step count (ICC 2,1 0.12-0.40). Percentage agreement with observed step count was highest for the StepWatch (mean 98%). The StepWatch and the Fitbit One worn on the ankle maintained accuracy in individuals who walked more slowly and with shorter strides but other devices were less accurate in these individuals. There were small numbers of participants for some gait parameters. The StepWatch showed the highest accuracy and closest agreement with observed step count. This device can be confidently used by researchers for accurate measurement of step counts in inpatient rehabilitation in individuals who walk slowly. If immediate feedback is desired, the Fitbit One when worn on the ankle would be the best choice for this population. © 2017 American Physical Therapy Association

The Influence of trisomy 21 on facial form and variability.

PubMed

Starbuck, John M; Cole, Theodore M; Reeves, Roger H; Richtsmeier, Joan T

2017-11-01

Triplication of chromosome 21 (trisomy 21) results in Down syndrome (DS), the most common live-born human aneuploidy. Individuals with DS have a unique facial appearance that can include form changes and altered variability. Using 3D photogrammatic images, 3D coordinate locations of 20 anatomical landmarks, and Euclidean Distance Matrix Analysis methods, we quantitatively test the hypothesis that children with DS (n = 55) exhibit facial form and variance differences relative to two different age-matched (4-12 years) control samples of euploid individuals: biological siblings of individuals with DS (n = 55) and euploid individuals without a sibling with DS (n = 55). Approximately 36% of measurements differ significantly between DS and DS-sibling samples, whereas 46% differ significantly between DS and unrelated control samples. Nearly 14% of measurements differ significantly in variance between DS and DS sibling samples, while 18% of measurements differ significantly in variance between DS and unrelated euploid control samples. Of those measures that showed a significant difference in variance, all were relatively increased in the sample of DS individuals. These results indicate that faces of children with DS are quantitatively more similar to their siblings than to unrelated euploid individuals and exhibit consistent, but slightly increased variation with most individuals falling within the range of normal variation established by euploid samples. These observations provide indirect evidence of the strength of the genetic underpinnings of the resemblance between relatives and the resistance of craniofacial development to genetic perturbations caused by trisomy 21, while underscoring the complexity of the genotype-phenotype map. © 2017 Wiley Periodicals, Inc.

Characterizing the roles of changing population size and selection on the evolution of flux control in metabolic pathways.

PubMed

Orlenko, Alena; Chi, Peter B; Liberles, David A

2017-05-25

Understanding the genotype-phenotype map is fundamental to our understanding of genomes. Genes do not function independently, but rather as part of networks or pathways. In the case of metabolic pathways, flux through the pathway is an important next layer of biological organization up from the individual gene or protein. Flux control in metabolic pathways, reflecting the importance of mutation to individual enzyme genes, may be evolutionarily variable due to the role of mutation-selection-drift balance. The evolutionary stability of rate limiting steps and the patterns of inter-molecular co-evolution were evaluated in a simulated pathway with a system out of equilibrium due to fluctuating selection, population size, or positive directional selection, to contrast with those under stabilizing selection. Depending upon the underlying population genetic regime, fluctuating population size was found to increase the evolutionary stability of rate limiting steps in some scenarios. This result was linked to patterns of local adaptation of the population. Further, during positive directional selection, as with more complex mutational scenarios, an increase in the observation of inter-molecular co-evolution was observed. Differences in patterns of evolution when systems are in and out of equilibrium, including during positive directional selection may lead to predictable differences in observed patterns for divergent evolutionary scenarios. In particular, this result might be harnessed to detect differences between compensatory processes and directional processes at the pathway level based upon evolutionary observations in individual proteins. Detecting functional shifts in pathways reflects an important milestone in predicting when changes in genotypes result in changes in phenotypes.

Social communication in siamangs (Symphalangus syndactylus): use of gestures and facial expressions.

PubMed

Liebal, Katja; Pika, Simone; Tomasello, Michael

2004-01-01

The current study represents the first systematic investigation of the social communication of captive siamangs (Symphalangus syndactylus). The focus was on intentional signals, including tactile and visual gestures, as well as facial expressions and actions. Fourteen individuals from different groups were observed and the signals used by individuals were recorded. Thirty-one different signals, consisting of 12 tactile gestures, 8 visual gestures, 7 actions, and 4 facial expressions, were observed, with tactile gestures and facial expressions appearing most frequently. The range of the signal repertoire increased steadily until the age of six, but declined afterwards in adults. The proportions of the different signal categories used within communicative interactions, in particular actions and facial expressions, also varied depending on age. Group differences could be traced back mainly to social factors or housing conditions. Differences in the repertoire of males and females were most obvious in the sexual context. Overall, most signals were used flexibly, with the majority performed in three or more social contexts and almost one-third of signals used in combination with other signals. Siamangs also adjusted their signals appropriately for the recipient, for example, using visual signals most often when the recipient was already attending (audience effects). These observations are discussed in the context of siamang ecology, social structure, and cognition.

The male-female gap in physician earnings: evidence from a public health insurance system.

PubMed

Theurl, Engelbert; Winner, Hannes

2011-10-01

Empirical evidence from US studies suggests that female physicians earn less than their male counterparts, on average. The earnings gap does not disappear when individual and market characteristics are controlled for. This paper investigates whether a gender earnings difference can also be observed in a health-care system predominantly financed by public insurance companies. Using a unique data set of physicians' earnings recorded by a public social security agency in an Austrian province between 2000 and 2004, we find a gender gap in average earnings of about 32%. A substantial share of this gap (20-47%) cannot be explained by individual and market characteristics, leaving labor market discrimination as one possible explanation for the observed gender earnings difference of physicians. Copyright © 2010 John Wiley & Sons, Ltd.

Wage differentials between college graduates with and without learning disabilities.

PubMed

Dickinson, David L; Verbeek, Roelant L

2002-01-01

Wage differential studies examining legally protected groups typically focus on gender or racial differences. Legislation also fully protects individuals with learning disabilities (LD). This article is the first to decompose wage differentials between adults with and without LD. An original data set of college graduates with documented LD was constructed, and these individuals were compared to a control group from the National Longitudinal Survey of Youth (NLSY). Our results show that much of the observed lower wages for individuals with LD is due to differences in productivity characteristics. However, there is an unexplained portion of the wage gap that could possibly be considered wage discrimination against individuals with LD. This possibility seems smaller due to the fact that the subsample of the employers who knew of the employee's learning disabilities did not appear to pay significantly lower wages to these individuals. Alternative hypotheses are discussed, as are sample-specific issues.

Why do we differ in number sense? Evidence from a genetically sensitive investigation☆

PubMed Central

Tosto, M.G.; Petrill, S.A.; Halberda, J.; Trzaskowski, M.; Tikhomirova, T.N.; Bogdanova, O.Y.; Ly, R.; Wilmer, J.B.; Naiman, D.Q.; Germine, L.; Plomin, R.; Kovas, Y.

2014-01-01

Basic intellectual abilities of quantity and numerosity estimation have been detected across animal species. Such abilities are referred to as ‘number sense’. For human species, individual differences in number sense are detectable early in life, persist in later development, and relate to general intelligence. The origins of these individual differences are unknown. To address this question, we conducted the first large-scale genetically sensitive investigation of number sense, assessing numerosity discrimination abilities in 837 pairs of monozygotic and 1422 pairs of dizygotic 16-year-old twin pairs. Univariate genetic analysis of the twin data revealed that number sense is modestly heritable (32%), with individual differences being largely explained by non-shared environmental influences (68%) and no contribution from shared environmental factors. Sex-Limitation model fitting revealed no differences between males and females in the etiology of individual differences in number sense abilities. We also carried out Genome-wide Complex Trait Analysis (GCTA) that estimates the population variance explained by additive effects of DNA differences among unrelated individuals. For 1118 unrelated individuals in our sample with genotyping information on 1.7 million DNA markers, GCTA estimated zero heritability for number sense, unlike other cognitive abilities in the same twin study where the GCTA heritability estimates were about 25%. The low heritability of number sense, observed in this study, is consistent with the directional selection explanation whereby additive genetic variance for evolutionary important traits is reduced. PMID:24696527

Clustering of physical inactivity in leisure, work, commuting and household domains among Brazilian adults.

PubMed

Del Duca, G F; Nahas, M V; de Sousa, T F; Mota, J; Hallal, P C; Peres, K G

2013-06-01

To identify the clustering of physical inactivity in leisure, work, commuting and household contexts, and the sociodemographic factors associated with the clustering of inactive behaviour in different domains among Brazilian adults. Cross-sectional population-based study. The study was performed in Florianopolis, capital of Santa Catarina, one of the southern states of Brazil, from September 2009 to January 2010. Adults aged 20-59 years were interviewed. Physical inactivity in each domain was defined as non-participation in specific physical activities, using a validated Brazilian questionnaire. Clustering of physical inactivity was identified by the ratio between observed prevalence and expected prevalence of 16 different combinations. Multinomial logistic regression was used in the analysis of sociodemographic factors associated with clustering of physical inactivity. Of the 1720 interviewees, the greatest differences between the observed and expected proportions were observed in simultaneous physical inactivity in the leisure and household domains for men, and physical inactivity in the leisure domain alone for women (59% and 88%, respectively); these differences were higher than expected if the behaviours were independent. Physical inactivity in two or more domains was observed more frequently in men and in individuals with a higher per-capita family income. Ageing was associated with physical inactivity in three or four domains. Physical inactivity was observed in different domains according to gender. Men and older individuals with a higher per-capita family income were more likely to exhibit physical inactivity when all domains were considered together. Copyright © 2013 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Perception of color emotions for single colors in red-green defective observers.

PubMed

Sato, Keiko; Inoue, Takaaki

2016-01-01

It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions). The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1) reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2) examine differences in color emotions related to the three cardinal channels in human color vision; and (3) explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP). Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance) as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth ratings in the red-green defective group revealed that luminance cone-contrast was a significant predictor in most red-green-defective individuals. Together, these results suggest that red-green defective observers tend to rely on the blue-yellow channel and luminance to compensate for the weak sensitivity of long- and medium-wavelength (L-M) cone-contrasts, when rating color warmth.

Perception of color emotions for single colors in red-green defective observers

PubMed Central

Inoue, Takaaki

2016-01-01

It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions). The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1) reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2) examine differences in color emotions related to the three cardinal channels in human color vision; and (3) explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP). Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance) as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth ratings in the red-green defective group revealed that luminance cone-contrast was a significant predictor in most red-green-defective individuals. Together, these results suggest that red-green defective observers tend to rely on the blue-yellow channel and luminance to compensate for the weak sensitivity of long- and medium-wavelength (L-M) cone-contrasts, when rating color warmth. PMID:27957394

Changes in Brain Network Efficiency and Working Memory Performance in Aging

PubMed Central

Stanley, Matthew L.; Simpson, Sean L.; Dagenbach, Dale; Lyday, Robert G.; Burdette, Jonathan H.; Laurienti, Paul J.

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory. PMID:25875001

Changes in brain network efficiency and working memory performance in aging.

PubMed

Stanley, Matthew L; Simpson, Sean L; Dagenbach, Dale; Lyday, Robert G; Burdette, Jonathan H; Laurienti, Paul J

2015-01-01

Working memory is a complex psychological construct referring to the temporary storage and active processing of information. We used functional connectivity brain network metrics quantifying local and global efficiency of information transfer for predicting individual variability in working memory performance on an n-back task in both young (n = 14) and older (n = 15) adults. Individual differences in both local and global efficiency during the working memory task were significant predictors of working memory performance in addition to age (and an interaction between age and global efficiency). Decreases in local efficiency during the working memory task were associated with better working memory performance in both age cohorts. In contrast, increases in global efficiency were associated with much better working performance for young participants; however, increases in global efficiency were associated with a slight decrease in working memory performance for older participants. Individual differences in local and global efficiency during resting-state sessions were not significant predictors of working memory performance. Significant group whole-brain functional network decreases in local efficiency also were observed during the working memory task compared to rest, whereas no significant differences were observed in network global efficiency. These results are discussed in relation to recently developed models of age-related differences in working memory.

Juvenile movement among different populations of cutthroat trout introduced as embryos to vacant habitat

USGS Publications Warehouse

Andrews, Tessa M.; Shepard, Bradley B.; Litt, Andrea R.; Kruse, Carter G.; Zale, Alexander V.; Kalinowski, Steven T.

2013-01-01

Translocations are frequently used to increase the abundance and range of endangered fishes. One factor likely to affect the outcome of translocations is fish movement. We introduced embryos from five Westslope Cutthroat Trout Oncorhynchus clarkii lewisi populations (both hatchery and wild) at five different locations within a fishless watershed. We then examined the movement of age-1 and age-2 fish and looked for differences in movement distance among source populations and among introduction sites; we also examined the interactions among age, population, and introduction site. At age 1, most individuals (90.9%) remained within 1,000 m their introduction sites. By age 2, the majority of individuals (58.3%) still remained within 1,000 m of their introduction site, but considerably more individuals had moved downstream, some more than 6,000 m from their introduction site. We observed a significant interaction between age and source population (F 4, 1077 = 15.45, P 4, 1077 = 11.39, P < 0.0008), so we presented results in the context of these interactions. Within age-groups, we observed differences in movement behavior among source populations and among donor populations of Westslope Cutthroat Trout. We discuss these findings in light of previous research on juvenile salmonid movement.

Effects of diabetes mellitus and systemic arterial hypertension on elderly patients' hearing.

PubMed

Rolim, Laurie Penha; Samelli, Alessandra Giannella; Moreira, Renata Rodrigues; Matas, Carla Gentile; Santos, Itamar de Souza; Bensenor, Isabela Martins; Lotufo, Paulo Andrade

2017-09-21

Chronic diseases can act as an accelerating factor in the auditory system degeneration. Studies on the association between presbycusis and diabetes mellitus and systemic arterial hypertension have shown controversial conclusions. To compare the initial audiometry (A1) with a subsequent audiometry (A2) performed after a 3 to 4-year interval in a population of elderly patients with diabetes mellitus and/or systemic arterial hypertension, to verify whether hearing loss in these groups is more accelerated when compared to controls without these clinical conditions. 100 elderly individuals participated in this study. For the auditory threshold assessment, a previous complete audiological evaluation (A1) and a new audiological evaluation (A2) performed 3-4 years after the first one was utilized. The participants were divided into four groups: 20 individuals in the diabetes mellitus group, 20 individuals in the systemic arterial hypertension group, 20 individuals in the diabetes mellitus/systemic arterial hypertension group and 40 individuals in the control group, matching them with each study group, according to age and gender. ANOVA and Kruskal-Wallis statistical tests were used, with a significance level set at 0.05. When comparing the mean annual increase in the auditory thresholds of the A1 with the A2 assessment, considering each study group and its respective control, it can be observed that there was no statistically significant difference for any of the frequencies for the diabetes mellitus group; for the systemic arterial hypertension group, significant differences were observed after 4kHz. For the diabetes mellitus and systemic arterial hypertension group, significant differences were observed at the frequencies of 500, 2kHz, 3kHz and 8kHz. It was observed that the systemic arterial hypertension group showed the greatest decrease in auditory thresholds in the studied segment when compared to the other groups, suggesting that among the three studied conditions, hypertension seems to have the greatest influence on hearing. Copyright © 2017 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

A Modular Mind? A Test Using Individual Data from Seven Primate Species

PubMed Central

Amici, Federica; Barney, Bradley; Johnson, Valen E.; Call, Josep; Aureli, Filippo

2012-01-01

It has long been debated whether the mind consists of specialized and independently evolving modules, or whether and to what extent a general factor accounts for the variance in performance across different cognitive domains. In this study, we used a hierarchical Bayesian model to re-analyse individual level data collected on seven primate species (chimpanzees, bonobos, orangutans, gorillas, spider monkeys, brown capuchin monkeys and long-tailed macaques) across 17 tasks within four domains (inhibition, memory, transposition and support). Our modelling approach evidenced the existence of both a domain-specific factor and a species factor, each accounting for the same amount (17%) of the observed variance. In contrast, inter-individual differences played a minimal role. These results support the hypothesis that the mind of primates is (at least partially) modular, with domain-specific cognitive skills undergoing different evolutionary pressures in different species in response to specific ecological and social demands. PMID:23284816

The idiosyncratic nature of confidence

PubMed Central

Navajas, Joaquin; Hindocha, Chandni; Foda, Hebah; Keramati, Mehdi; Latham, Peter E; Bahrami, Bahador

2017-01-01

Confidence is the ‘feeling of knowing’ that accompanies decision making. Bayesian theory proposes that confidence is a function solely of the perceived probability of being correct. Empirical research has suggested, however, that different individuals may perform different computations to estimate confidence from uncertain evidence. To test this hypothesis, we collected confidence reports in a task where subjects made categorical decisions about the mean of a sequence. We found that for most individuals, confidence did indeed reflect the perceived probability of being correct. However, in approximately half of them, confidence also reflected a different probabilistic quantity: the perceived uncertainty in the estimated variable. We found that the contribution of both quantities was stable over weeks. We also observed that the influence of the perceived probability of being correct was stable across two tasks, one perceptual and one cognitive. Overall, our findings provide a computational interpretation of individual differences in human confidence. PMID:29152591

Levels of Social Play: Observing and Recording Preschoolers.

ERIC Educational Resources Information Center

Barbakoff, Sondra; Yo, Yang Pei

Noting that observing preschool children at play allows teachers to understand how individual children develop their social skills, this article describes different levels of social play and shows how teachers may use a running record and check list to assess such play. Children are described as engaging in onlooker play, solitary play, parallel…

Pneumonia Frequencies with Different Enteral Tube Feeding Access Sites.

ERIC Educational Resources Information Center

Taylor, Henry M.

2002-01-01

Over a 24-month period, 25 adults with mental retardation being fed via a gastrostomy tube experienced 40 cases of pneumonia during 508 person-months of observations, whereas 5 individuals being fed via a jejunostromy tube did not experience any pneumonia during 96 person-months of observation. (Contains references.) (Author/CR)

Pain Management in Intellectually Disabled Children: Assessment, Treatment, and Translational Research

ERIC Educational Resources Information Center

Valkenburg, Abraham J.; van Dijk, Monique; de Klein, Annelies; van den Anker, Johannes N.; Tibboel, Dick

2010-01-01

The primary focus of pain research in intellectually disabled individuals is still on pain assessment. Several observational pain assessment scales are available, each with its own characteristics, its own target group and its own validated use. Observational studies report differences in the treatment of intra- and postoperative pain of…

Analysis of algorithms for predicting canopy fuel

Treesearch

Katharine L. Gray; Elizabeth Reinhardt

2003-01-01

We compared observed canopy fuel characteristics with those predicted by existing biomass algorithms. We specifically examined the accuracy of the biomass equations developed by Brown (1978. We used destructively sampled data obtained at 5 different study areas. We compared predicted and observed quantities of foliage and crown biomass for individual trees in our study...

Prevalence of Dental Anomalies in Permanent Dentition of Brazilian Individuals with Down Syndrome

PubMed Central

Cuoghi, Osmar Aparecido; Topolski, Francielle; Perciliano de Faria, Lorraine; Occhiena, Carla Machado; Ferreira, Nancy dos Santos Pinto; Ferlin, Camila Ribeiro; Rogério de Mendonça, Marcos

2016-01-01

Objective: The aim of this study was to evaluate the incidence of dental anomalies in the permanent dentition of individuals with Down Syndrome (DS) to increase the knowledge on the dental issues in this syndrome. Method: One hundred and five panoramic X-rays of patients with DS (61 males and 44 females), aged 7 to 42 years were used. The data were statistically analyzed using bivariate analyses test (p <0.05). Results: Dental anomalies were observed in 50.47% of the sample. More than one anomaly was observed in 9.52% of the individuals. The most frequent dental anomalies were hypodontia and microdontia (16.19%), followed by retained tooth (10.47%), taurodontism (9.52%), supernumerary teeth (5.71%), macrodontia (2.85%) and root dilaceration (0.95%). There was no statistically significant difference between genders for any of the anomalies. Conclusion: A high prevalence of dental anomalies was observed in individuals with DS. The results of the present study reinforce the importance of good dental care, offering a greater basis for professionals who provide dental service to these patients. PMID:27733874

Prevalence of Dental Anomalies in Permanent Dentition of Brazilian Individuals with Down Syndrome.

PubMed

Cuoghi, Osmar Aparecido; Topolski, Francielle; Perciliano de Faria, Lorraine; Occhiena, Carla Machado; Ferreira, Nancy Dos Santos Pinto; Ferlin, Camila Ribeiro; Rogério de Mendonça, Marcos

2016-01-01

The aim of this study was to evaluate the incidence of dental anomalies in the permanent dentition of individuals with Down Syndrome (DS) to increase the knowledge on the dental issues in this syndrome. One hundred and five panoramic X-rays of patients with DS (61 males and 44 females), aged 7 to 42 years were used. The data were statistically analyzed using bivariate analyses test ( p <0.05). Dental anomalies were observed in 50.47% of the sample. More than one anomaly was observed in 9.52% of the individuals. The most frequent dental anomalies were hypodontia and microdontia (16.19%), followed by retained tooth (10.47%), taurodontism (9.52%), supernumerary teeth (5.71%), macrodontia (2.85%) and root dilaceration (0.95%). There was no statistically significant difference between genders for any of the anomalies. A high prevalence of dental anomalies was observed in individuals with DS. The results of the present study reinforce the importance of good dental care, offering a greater basis for professionals who provide dental service to these patients.

Measuring changes in the mass of single subcellular organelles using x-ray microscopy

NASA Astrophysics Data System (ADS)

Goncz, Kaarin K.; Moronne, Mario M.; Lin, W.; Rothman, Stephen S.

1993-01-01

Using quantitative scanning transmission x-ray microscopy, zymogen granules isolated from pancreatic acinar cells were observed suspended in aqueous medium at 50 nm resolution. From 3.64 nm x-ray absorption data, the protein content and rate of protein efflux from individual granules were determined. This was accomplished with a specially designed silicon nitride based wet-cell that allowed continuous perfusion and monitoring of individual granules in a variety of different aqueous environments. Granules suspended in 300 mM sucrose, 5 mM phosphate buffer (pH 6.0) were observed to continuously decrease in size and protein content over a period of several hours. Sudden lysis of the granules was not observed. From the flux data, the apparent protein permeability coefficients for individual granules were determined to range from 1 - 10 X 10-10 cm/sec with an average of 4.78 +/- 3.0 X 10-10 cm/sec. We believe this is the first quantitative population profile determined for a subcellular organelle developed from measurements of individual members of the population.

Acrocentric chromosome associations in man.

PubMed Central

Jacobs, P A; Mayer, M; Morton, N E

1976-01-01

Heterogeneity among chromosomes was found to be a highly significant source of variation for association proportions, while culture, slide, and observer were negligible sources of variation for association proportions although important for numbers of associations. The consequences of these results for tests of group differences are discussed. It seems evident that each pair of acrocentric chromosomes has its own characteristic probability of entering into association. This is presumably a combination of the probability for each individual member of the pair, a proposition easily tested utilizing acrocentric chromosomes carrying polymorphisms which allow each member of the pair to be individually recognized. A mathematical theory for pairwise satellite association was developed and shown to fit observations on banded chromosomes. While we found very significant heterogeneity among individuals in the frequency with which different chromosomes entered into associations, there was no significant evidence for preferential association between any particular chromosomes, either heterologous or homologous. This finding in our material of apparently random associations between different chromosomes is contrary to claims made by other investigators and should be tested on other material. No correlation was found between the phenotype of the chromosome, as judged by cytogenetic polymorphisms, and its probability of association. PMID:795295

Perceptual “vowel spaces” of cochlear implant users: Implications for the study of auditory adaptation to spectral shift

PubMed Central

Harnsberger, James D.; Svirsky, Mario A.; Kaiser, Adam R.; Pisoni, David B.; Wright, Richard; Meyer, Ted A.

2012-01-01

Cochlear implant (CI) users differ in their ability to perceive and recognize speech sounds. Two possible reasons for such individual differences may lie in their ability to discriminate formant frequencies or to adapt to the spectrally shifted information presented by cochlear implants, a basalward shift related to the implant’s depth of insertion in the cochlea. In the present study, we examined these two alternatives using a method-of-adjustment (MOA) procedure with 330 synthetic vowel stimuli varying in F1 and F2 that were arranged in a two-dimensional grid. Subjects were asked to label the synthetic stimuli that matched ten monophthongal vowels in visually presented words. Subjects then provided goodness ratings for the stimuli they had chosen. The subjects’ responses to all ten vowels were used to construct individual perceptual “vowel spaces.” If CI users fail to adapt completely to the basalward spectral shift, then the formant frequencies of their vowel categories should be shifted lower in both F1 and F2. However, with one exception, no systematic shifts were observed in the vowel spaces of CI users. Instead, the vowel spaces differed from one another in the relative size of their vowel categories. The results suggest that differences in formant frequency discrimination may account for the individual differences in vowel perception observed in cochlear implant users. PMID:11386565

SU90. The Relationship Between Changes in Cortical Thickness and Cognitive Empathy in Individuals With Schizophrenia

PubMed Central

Petersen, Julie; Cobia, Derin

2017-01-01

Abstract Background: Prior studies suggest the thickness of the medial prefrontal cortex (mPFC), inferior frontal gyrus (IFG), anterior mid-cingulate (aMCC), insula (INS), supplementary motor area (SMA), temporo-parietal junction (TPJ), and precuneus (PREC) are associated with cognitive empathy, which is impaired in schizophrenia. The current study examines the relationship between cognitive empathy performance at baseline and changes in cortical thickness in both healthy controls and individuals with schizophrenia. Methods: Thirty clinically stable community-dwelling individuals with schizophrenia and 26 healthy controls group-matched on demographic variables completed a cognitive empathy task and structural magnetic resonance imaging at 2 time points approximately 24 months apart. Difference scores representing change in cortical thickness were calculated as: follow-up − baseline = difference score. Repeated-measures ANOVAs evaluated changes in cortical thickness between groups. OLS regressions were computed to determine the effect of cognitive empathy performance on change in cortical thickness. Results: Change in cortical thickness in individuals with schizophrenia differed from controls in the mPFC, IFG, INS, SMA, TPJ, and PREC 
(all P < .05) between baseline and 2-year follow-up. Among individuals with schizophrenia, we found that baseline cognitive empathy performance predicted changes in cortical thickness in the left (b = 0.346, t(28) = 3.752, P < .001) and right precuneus (b = 0.399, t(28) = 3.649, P < .001), and left (b = 0.319, t(28) = 3.141, P = .004) and right TPJ (b = 0.294, t(28) = 2.7, P = .012). We did not observe a relationship between baseline cognitive empathy performance and changes in cortical thickness of the empathy circuit in controls. Conclusion: Consistent with prior studies, we observed that individuals with schizophrenia had greater thinning in cortical regions, which were specific to the empathy circuit. Also, we observed that baseline cognitive empathy performance predicted greater cortical thinning among individuals with schizophrenia. It is possible that individuals with schizophrenia who have greater cognitive empathy are more likely to engage in social activities, which might be neuroprotective. Future research is needed to evaluate these relationships.

Individually Coded Telemetry: a Tool for Studying Heart Rate and Behaviour in Reindeer Calves

PubMed Central

Eloranta, E; Norberg, H; Nilsson, A; Pudas, T; Säkkinen, H

2002-01-01

The aim of the study was to test the performance of a silver wire modified version of the coded telemetric heart rate monitor Polar Vantage NV™ (PVNV) and to measure heart rate (HR) in a group of captive reindeer calves during different behaviour. The technical performance of PVNV HR monitors was tested in cold conditions (-30°C) using a pulse generator and the correlation between generated pulse and PVNV values was high (r = 0.9957). The accuracy was tested by comparing the HR obtained with the PVNV monitor with the standard ECG, and the correlation was significant (r = 0.9965). Both circadian HR and HR related to behavioural pattern were recorded. A circadian rhythm was observed in the HR in reindeer with a minimum during night and early morning hours and maximum at noon and during the afternoon, the average HR of the reindeer calves studied being 42.5 beats/min in February. The behaviour was recorded by focal individual observations and the data was synchronized with the output of the HR monitors. Running differed from all other behavioural categories in HR. Inter-individual differences were seen expressing individual responses to external and internal stimuli. The silver wire modified Polar Vantage NV™ provides a suitable and reliable tool for measuring heart rate in reindeer, also in natural conditions. PMID:12564543

Welfare assessment in broiler farms: transect walks versus individual scoring.

PubMed

Marchewka, J; Watanabe, T T N; Ferrante, V; Estevez, I

2013-10-01

Current scientific approaches to welfare assessment in broilers are based on individual sampling that can be time consuming under field conditions. On the other hand, farmers conduct routine checks based on walks through the house to screen birds' health condition. We adapted the walks through following line transect methodology used in wildlife studies to explore their feasibility as a welfare assessment tool. The aim of this study was to compare broiler welfare assessed by individual sampling and transect walks. We evaluated 6 identically managed flocks. For individual sampling, we collected measures on 150 birds, including weight, breast dirtiness, hock and footpad dermatitis, lameness, and immobility. Transect observations were conducted by slowly walking on randomized paths within each house recording: immobility, lameness, back dirtiness, sickness, agony, and dead. Transect walks allowed detection of small variations (P < 0.003) in the prevalence of most welfare indicators considered with consistency in interobserver reliability (P ≥ 0.05). In addition, assessments across transects were highly consistent (P ≥ 0.05). Individual sampling was also sensitive to differences across houses (P < 0.01) with the exception of immobility (P = 0.783). No differences were found across sampling locations (P ≥ 0.05). However, both methods differed greatly in the frequency of the incidence of the parameters considered. For example, immobility varied from 0.2 ± 0.02% for transect walks to 4 ± 2.3% for individual sampling, whereas lameness varied between 0.8 ± 0.07% and 24.2 ± 4.7% for transect and samplings, respectively. It is possible that the transect approach may have overlooked walking deficiencies because a large number of birds were scored, although if this was the case, the consistency obtained in the scoring across observers and transects would be surprising. Differences may also be related to possibly biased individual sampling procedures, where less mobile and passive individuals may be more likely to be caught. Furthermore the procedure may cause fatigue and fear reactions reducing mobility. Current study provides new insights into constraints and advantages of broiler on-farm assessment methods, which should be considered for designing on-farm welfare assessment protocols.

Keeping memories at an arm's length: vantage point of trauma memories.

PubMed

Kenny, Lucy M; Bryant, Richard A

2007-08-01

This study investigated the relationship between memory vantage point and avoidance following trauma. Sixty trauma survivors with differing levels of avoidance were interviewed about the vantage point of their memory for trauma, a positive memory, and a neutral memory. Avoidant individuals were more likely to remember their trauma from an observer perspective than individuals with a lower level of avoidance. Avoidance did not influence vantage point for positive or neutral memories. These data support the proposal that adoption of the observer vantage point for trauma memories may serve an avoidant function for people affected by trauma.

Evidence that Gender Differences in Social Dominance Orientation Result from Gendered Self-Stereotyping and Group-Interested Responses to Patriarchy

ERIC Educational Resources Information Center

Schmitt, Michael T.; Wirth, James H.

2009-01-01

Numerous studies have found that, compared to women, men express higher levels of social dominance orientation (SDO), an individual difference variable reflecting support for unequal, hierarchical relationships between groups. Recent research suggests that the often-observed gender difference in SDO results from processes related to gender group…

The Role of Musical Experience in Hemispheric Lateralization of Global and Local Auditory Processing.

PubMed

Black, Emily; Stevenson, Jennifer L; Bish, Joel P

2017-08-01

The global precedence effect is a phenomenon in which global aspects of visual and auditory stimuli are processed before local aspects. Individuals with musical experience perform better on all aspects of auditory tasks compared with individuals with less musical experience. The hemispheric lateralization of this auditory processing is less well-defined. The present study aimed to replicate the global precedence effect with auditory stimuli and to explore the lateralization of global and local auditory processing in individuals with differing levels of musical experience. A total of 38 college students completed an auditory-directed attention task while electroencephalography was recorded. Individuals with low musical experience responded significantly faster and more accurately in global trials than in local trials regardless of condition, and significantly faster and more accurately when pitches traveled in the same direction (compatible condition) than when pitches traveled in two different directions (incompatible condition) consistent with a global precedence effect. In contrast, individuals with high musical experience showed less of a global precedence effect with regards to accuracy, but not in terms of reaction time, suggesting an increased ability to overcome global bias. Further, a difference in P300 latency between hemispheres was observed. These findings provide a preliminary neurological framework for auditory processing of individuals with differing degrees of musical experience.

An Expressive Bodily Movement Repertoire for Marimba Performance, Revealed through Observers' Laban Effort-Shape Analyses, and Allied Musical Features: Two Case Studies

PubMed Central

Broughton, Mary C.; Davidson, Jane W.

2016-01-01

Musicians' expressive bodily movements can influence observers' perception of performance. Furthermore, individual differences in observers' music and motor expertise can shape how they perceive and respond to music performance. However, few studies have investigated the bodily movements that different observers of music performance perceive as expressive, in order to understand how they might relate to the music being produced, and the particular instrument type. In this paper, we focus on marimba performance through two case studies—one solo and one collaborative context. This study aims to investigate the existence of a core repertoire of marimba performance expressive bodily movements, identify key music-related features associated with the core repertoire, and explore how observers' perception of expressive bodily movements might vary according to individual differences in their music and motor expertise. Of the six professional musicians who observed and analyzed the marimba performances, three were percussionists and experienced marimba players. Following training, observers implemented the Laban effort-shape movement analysis system to analyze marimba players' bodily movements that they perceived as expressive in audio-visual recordings of performance. Observations that were agreed by all participants as being the same type of action at the same location in the performance recording were examined in each case study, then across the two studies. A small repertoire of bodily movements emerged that the observers perceived as being expressive. Movements were primarily allied to elements of the music structure, technique, and expressive interpretation, however, these elements appeared to be interactive. A type of body sway movement and more localized sound generating actions were perceived as expressive. These movements co-occurred and also appeared separately. Individual participant data revealed slightly more variety in the types and locations of actions observed, with judges revealing preferences for observing particular types of expressive bodily movements. The particular expressive bodily movements that are produced and perceived in marimba performance appear to be shaped by music-related and sound generating features, musical context, and observer music and motor expertise. With an understanding of bodily movements that are generated and perceived as expressive, embodied music performance training programs might be developed to enhance expressive performer-audience communication. PMID:27630585

An Expressive Bodily Movement Repertoire for Marimba Performance, Revealed through Observers' Laban Effort-Shape Analyses, and Allied Musical Features: Two Case Studies.

PubMed

Broughton, Mary C; Davidson, Jane W

2016-01-01

Musicians' expressive bodily movements can influence observers' perception of performance. Furthermore, individual differences in observers' music and motor expertise can shape how they perceive and respond to music performance. However, few studies have investigated the bodily movements that different observers of music performance perceive as expressive, in order to understand how they might relate to the music being produced, and the particular instrument type. In this paper, we focus on marimba performance through two case studies-one solo and one collaborative context. This study aims to investigate the existence of a core repertoire of marimba performance expressive bodily movements, identify key music-related features associated with the core repertoire, and explore how observers' perception of expressive bodily movements might vary according to individual differences in their music and motor expertise. Of the six professional musicians who observed and analyzed the marimba performances, three were percussionists and experienced marimba players. Following training, observers implemented the Laban effort-shape movement analysis system to analyze marimba players' bodily movements that they perceived as expressive in audio-visual recordings of performance. Observations that were agreed by all participants as being the same type of action at the same location in the performance recording were examined in each case study, then across the two studies. A small repertoire of bodily movements emerged that the observers perceived as being expressive. Movements were primarily allied to elements of the music structure, technique, and expressive interpretation, however, these elements appeared to be interactive. A type of body sway movement and more localized sound generating actions were perceived as expressive. These movements co-occurred and also appeared separately. Individual participant data revealed slightly more variety in the types and locations of actions observed, with judges revealing preferences for observing particular types of expressive bodily movements. The particular expressive bodily movements that are produced and perceived in marimba performance appear to be shaped by music-related and sound generating features, musical context, and observer music and motor expertise. With an understanding of bodily movements that are generated and perceived as expressive, embodied music performance training programs might be developed to enhance expressive performer-audience communication.

Elevated Outcome-Anticipation and Outcome-Evaluation ERPs Associated with a Greater Preference for Larger-But-Delayed Rewards

PubMed Central

Pornpattananangkul, Narun; Nadig, Ajay; Heidinger, Storm; Walden, Keegan; Nusslock, Robin

2017-01-01

Although waiting for a reward reduces or discounts its value, some people have a stronger tendency to wait for larger rewards and forgo smaller-but-immediate rewards. This ability to delay gratification is captured by individual differences in so-called inter-temporal choices in which individuals are asked to choose between larger-but-delayed versus smaller-but-immediate rewards. The current study used event-related potentials (ERPs) to examine whether enhancement in two neuro-cognitive processes, outcome-anticipation and outcome-evaluation, modulate individual variability in inter-temporal responses. After completing a behavioral inter-temporal choice task, 34 participants performed an ERP gambling task. From this ERP task, we separately examined individual differences in outcome-anticipation (Stimulus-Preceding Negativity, SPN), early outcome-evaluation (Feedback-Related Negativity; FRN) and late outcome-evaluation (P3). We observed that both elevated outcome-anticipation (SPN) and late outcome-evaluation (P3) neural processes predicted a stronger preference toward larger-but-delayed rewards. No relationship was observed between inter-temporal responses and early outcome-evaluation (FRN), indicating that the relationship between outcome-evaluation and inter-temporal responses was specific to the late outcome-evaluation processing stream. Moreover, multiple regression analyses indicated that the SPN and P3 independently modulate individual differences in inter-temporal responses, suggesting separate mechanisms underlie the relationship between these two neuro-cognitive processes and inter-temporal responses. Accordingly, we identify two potential neural-cognitive modulators of individual variability in inter-temporal responses. We discuss the mechanisms underlying these modulators in terms of anticipation-related processing (SPN) and a saliency-bias toward gain (compared to loss) outcomes (P3). PMID:28224457

Retirement Sequences of Older Americans: Moderately Destandardized and Highly Stratified Across Gender, Class, and Race.

PubMed

Calvo, Esteban; Madero-Cabib, Ignacio; Staudinger, Ursula M

2017-06-06

A destandardization of labor-force patterns revolving around retirement has been observed in recent literature. It is unclear, however, to which degree and of which kind. This study looked at sequences rather than individual statuses or transitions and argued that differentiating older Americans' retirement sequences by type, order, and timing and considering gender, class, and race differences yields a less destandardized picture. Sequence analysis was employed to analyze panel data from the Health and Retirement Study (HRS) for 7,881 individuals observed 6 consecutive times between ages 60-61 and 70-71. As expected, types of retirement sequences were identified that cannot be subsumed under the conventional model of complete retirement from full-time employment around age 65. However, these retirement sequences were not entirely destandardized, as some irreversibility and age-grading persisted. Further, the degree of destandardization varied along gender, class, and race. Unconventional sequences were archetypal for middle-level educated individuals and Blacks. Also, sequences for women and individuals with lower education showed more unemployment and part-time jobs, and less age-grading. A sequence-analytic approach that models group differences uncovers misjudgments about the degree of destandardization of retirement sequences. When a continuous process is represented as individual transitions, the overall pattern of retirement sequences gets lost and appears destandardized. These patterns get further complicated by differences in social structures by gender, class, and race in ways that seem to reproduce advantages that men, more highly educated individuals, and Whites enjoy in numerous areas over the life course. © The Author 2017. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Cognitive world: Neuropsychology of individual differences.

PubMed

Ardila, Alfredo; Rosselli, Monica

2018-01-01

It is proposed that depending upon the specific pattern of cognitive abilities, each individual lives in an idiosyncratic "cognitive world." Brain pathology can be associated with some disturbed abilities, and frequently experiential changes (i.e., how the world is understood) are observed. Because these patients often are aware of their intellectual changes, they may represent excellent models to illustrate the diversity of cognitive interpretations an individual can have about the surrounding environmental conditions. Four neuropsychology cases are presented to illustrate this point: (a) prosopagnosia associated with spatial agnosia; (b) Gerstmann's syndrome; (c) dysexecutive syndrome due to a head injury; and, (d) patient with Capgras' syndrome associated with a left temporal cyst. It is further emphasized that non-brain damaged people present an enormous-but usually overlooked-dispersion in different cognitive domains, resulting in specific and idiosyncratic patterns of cognitive abilities. It is concluded that the concept of "cognitive world" in neuropsychology can parallel the concept of "perceptual world" introduced by von Uexküll in biology, which assumes that different animal species live in idiosyncratic perceptual worlds, available and knowable by the differences in their sensory system abilities. That is, different individuals live in idiosyncratic cognitive worlds, owing to their differences in cognitive abilities.

[Short-term death dynamics of trees in natural secondary poplar-birch forest in Changbai Mountains of Northeast China].

PubMed

Zhang, Zhao-Chen; Hao, Zhan-Qing; Ye, Ji; Lin, Fei; Yuan, Zuo-Qiang; Xing, Ding-Liang; Shi, Shuai; Wang, Xu-gao

2013-02-01

Taking the 5 hm2 sampling plot in the natural secondary poplar-birch forest in Changbai Mountains as test object, and based on the two census data in 2005 and 2010, an analysis was made on the main tree species composition and quantity, size class distribution of dead individuals, and regeneration characteristics of the main tree species in different habitat types of the plot in 2005-2010. In the five years, the species number of the individuals with DBH> or = 1 cm increased from 46 to 47, among which, 3 species were newly appeared, and 2 species were disappeared. The number of the individuals changed from 16509 to 15027, among which, 2150 individuals died, accounting for 13% of the whole individuals in 2005, and 668 individuals were newly increased. The basal area of the trees increased from 28.79 m2.m-2 to 30.55 m2.m-2, with that of 41 species increased while that of 6 species decreased. The decrease of the basal area of Betula platyphylla and Populus davidiana accounted for 72.3% of the total decrease. Small individuals had higher mortality, as compared with large ones, and the mortality of the individuals with DBH<5 cm occupied 65% of the total. B. platyphylla and P. davidiana contributed most in the dead individuals with large DBH. No difference was observed in the tree mortality among different habitat types, but the mortality of the individuals with different size classes showed greater variation.

Effect of bilateral stimulation of the subthalamic nucleus on different speech subsystems in patients with Parkinson's disease.

PubMed

Pützer, Manfred; Barry, William J; Moringlane, Jean Richard

2008-12-01

The effect of deep brain stimulation on the two speech-production subsystems, articulation and phonation, of nine Parkinsonian patients is examined. Production parameters (stop closure voicing; stop closure, VOT, vowel) in fast syllable-repetitions were defined and measured and quantitative, objective metrics of vocal fold function were obtained during vowel production. Speech material was recorded for patients (with and without stimulation) and for a reference group of healthy control speakers. With stimulation, precision of the glottal and supraglottal articulation as well as the phonatory function is reduced for some individuals, whereas for other individuals an improvement is observed. Importantly, the improvement or deterioration is determined not only on the basis of the direction of parameter change but also on the individuals' position relative to the healthy control data. This study also notes differences within an individual in the effects of stimulation on the two speech subsystems. These findings qualify the value of global statements about the effect of neurostimulatory operations on Parkinsonian patients. They also underline the importance of careful consideration of individual differences in the effect of deep brain stimulation on different speech subsystems.

Individuality and universality in the growth-division laws of single E. coli cells

NASA Astrophysics Data System (ADS)

Kennard, Andrew S.; Osella, Matteo; Javer, Avelino; Grilli, Jacopo; Nghe, Philippe; Tans, Sander J.; Cicuta, Pietro; Cosentino Lagomarsino, Marco

2016-01-01

The mean size of exponentially dividing Escherichia coli cells in different nutrient conditions is known to depend on the mean growth rate only. However, the joint fluctuations relating cell size, doubling time, and individual growth rate are only starting to be characterized. Recent studies in bacteria reported a universal trend where the spread in both size and doubling times is a linear function of the population means of these variables. Here we combine experiments and theory and use scaling concepts to elucidate the constraints posed by the second observation on the division control mechanism and on the joint fluctuations of sizes and doubling times. We found that scaling relations based on the means collapse both size and doubling-time distributions across different conditions and explain how the shape of their joint fluctuations deviates from the means. Our data on these joint fluctuations highlight the importance of cell individuality: Single cells do not follow the dependence observed for the means between size and either growth rate or inverse doubling time. Our calculations show that these results emerge from a broad class of division control mechanisms requiring a certain scaling form of the "division hazard rate function," which defines the probability rate of dividing as a function of measurable parameters. This "model free" approach gives a rationale for the universal body-size distributions observed in microbial ecosystems across many microbial species, presumably dividing with multiple mechanisms. Additionally, our experiments show a crossover between fast and slow growth in the relation between individual-cell growth rate and division time, which can be understood in terms of different regimes of genome replication control.

Assessment of unconstrained cerebrovascular reactivity marker for large age-range FMRI studies.

PubMed

Kannurpatti, Sridhar S; Motes, Michael A; Biswal, Bharat B; Rypma, Bart

2014-01-01

Breath hold (BH), a commonly used task to measure cerebrovascular reactivity (CVR) in fMRI studies varies in outcome among individuals due to subject-physiology and/or BH-inspiration/expiration differences (i.e., performance). In prior age-related fMRI studies, smaller task-related BOLD response variability is observed among younger than older individuals. Also, a linear CVR versus task relationship exists in younger individuals which maybe useful to test the accuracy of CVR responses in older groups. Hence we hypothesized that subject-related physiological and/or BH differences, if present, may compromise CVR versus task linearity in older individuals. To test the hypothesis, empirical BH versus task relationships from motor and cognitive areas were obtained in younger (mean age = 26 years) and older (mean age = 58 years) human subjects. BH versus task linearity was observed only in the younger group, confirming our hypothesis. Further analysis indicated BH responses and its variability to be similar in both younger and older groups, suggesting that BH may not accurately represent CVR in a large age range. Using the resting state fluctuation of amplitude (RSFA) as an unconstrained alternative to BH, subject-wise correspondence between BH and RSFA was tested. Correlation between BH versus RSFA was significant within the motor but was not significant in the cognitive areas in the younger and was completely disrupted in both areas in the older subjects indicating that BH responses are constrained by subject-related physiology and/or performance-related differences. Contrasting BH to task, RSFA-task relationships were independent of age accompanied by age-related increases in CVR variability as measured by RSFA, not observed with BH. Together the results obtained indicate that RSFA accurately represents CVR in any age range avoiding multiple and yet unknown physiologic and task-related pitfalls of BH.

Periapical cytokine expression in sickle cell disease.

PubMed

Ferreira, Shirlene Barbosa Pimentel; de Brito, Luciana Carla Neves; Oliveira, Michelle Pimenta; Maciel, Kamilla Faria; Martelli Júnior, Hercílio; Vieira, Leda Quercia; Sobrinho, Antônio Paulino Ribeiro

2015-03-01

Sickle cell anemia (SCA) is the most prevalent genetic disease worldwide. Patients with SCA exhibit increased levels of proinflammatory mediators as part of a permanently activated immunoinflammatory status. The aim of this study was to evaluate the mRNA expression levels of the cytokines interferon (IFN-γ), tumor necrosis factor, interleukin (IL-1β, IL-17A, IL-10), receptor activator for nuclear factor kappa B ligand, and the chemokines CCL2/MCP-1 and CCL5 in the periapical interstitial fluid from SCA individuals compared with healthy individuals. Samples were collected from 12 teeth of SCA patients and 12 non-SCA patients with apical periodontitis. In addition, 12 teeth were sampled from the periapical region of healthy patients with vital pulp (control). The expression of cytokine mRNA was detected by using real-time polymerase chain reaction. The expression of mRNA for the Th1-associated cytokines IFN-γ, tumor necrosis factor-α, and IL-1β were significantly higher in SCA individuals than in the control individuals (P < .05). Among Th1-associated cytokines, only IFN-γ was significantly increased in non-SCA compared with control patients (vital pulp). The expression of IL-17A mRNA was significant higher in SCA cases than in control samples (P < .05), whereas the IL-10 mRNA expression was significantly increased in SCA and non-SCA individuals when compared with the control group. Similar levels of receptor activator for nuclear factor kappa B ligand, CCL2, and CCL5 mRNA expression were observed in all samples. However, no significant differences were observed in the expression of cytokine or chemokine mRNA between SCA and non-SCA individuals (P > .05). The results were able to demonstrate that SCA patients presented prone proinflammatory ability, despite the fact that any differences in periapical immune responses between SCA and non-SCA individuals were not observed. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Individual species affect plant traits structure in their surroundings: evidence of functional mechanisms of assembly.

PubMed

Chacón-Labella, Julia; de la Cruz, Marcelino; Pescador, David S; Escudero, Adrián

2016-04-01

Evaluating community assembly through the use of functional traits is a promising tool for testing predictions arising from Niche and Coexistence theories. Although interactions among neighboring species and their inter-specific differences are known drivers of coexistence with a strong spatial signal, assessing the role of individual species on the functional structure of the community at different spatial scales remains a challenge. Here, we ask whether individual species exert a measurable effect on the spatial organization of different functional traits in local assemblages. We first propose and compute two functions that describe different aspects of functional trait organization around individual species at multiple scales: individual weighted mean area relationship and individual functional diversity area relationship. Secondly, we develop a conceptual model on the relationship and simultaneous variation of these two metrics, providing five alternative scenarios in response to the ability of some target species to modify its neighbor environment and the possible assembly mechanisms involved. Our results show that some species influence the spatial structure of specific functional traits, but their effects were always restricted to the finest spatial scales. In the basis of our conceptual model, the observed patterns point to two main mechanisms driving the functional structure of the community at the fine scale, "biotic" filtering meditated by individual species and resource partitioning driven by indirect facilitation rather than by competitive mechanisms.

Effects of high-intensity resistance training on strength, mobility, balance, and fatigue in individuals with multiple sclerosis: a randomized controlled trial.

PubMed

Hayes, Heather A; Gappmaier, Eduard; LaStayo, Paul C

2011-03-01

Resistance exercise via negative, eccentrically induced work (RENEW) has been shown to be associated with improvements in strength, mobility, and balance in multiple clinical populations. However, RENEW has not been reported for individuals with multiple sclerosis (MS). Nineteen individuals with MS (8 men, 11 women; age mean = 49 ± 11 years; Expanded Disability Status Scale [EDSS] mean = 5.2 ± 0.9) were randomized into either standard exercise (STAND) or standard exercise and RENEW training (RENEW) for 3×/week for 12 weeks. Outcome measures were lower extremity strength (hip/knee flexion and extension, ankle plantar and dorsiflexion, and the sum of these individual values [sum strength]); Timed Up and Go (TUG), 10-m walk, self-selected pace (TMWSS) and maximal-pace (TMWMP), stair ascent (S-A) and descent (S-D) and 6-Minute Walk Test (6MWT), Berg Balance Scale (BBS), Fatigue Severity Scale (FSS). No significant time effects or interactions were observed for strength, TUG, TMWSS, TMWMP, or 6MWT. However, the mean difference in sum strength in the RENEW group was 38.60 (representing a 15% increase) compared to the sum strength observed in the STAND group with a mean difference of 5.58 (a 2% increase). A significant interaction was observed for S-A, S-D, and BBS as the STAND group improved whereas the RENEW group did not improve in these measures. Contrary to results in other populations, the addition of eccentric training to standard exercises did not result in significantly greater lower extremity strength gains in this group of individuals with MS. Further this training was not as effective as standard exercise alone in improving balance or the ability to ascend and descend stairs. Following data collection, reassessment of required sample size indicates we were likely underpowered to detect strength differences between groups.

Catalog of infrared observations

NASA Technical Reports Server (NTRS)

Gezari, D. Y.; Schmitz, M.; Mead, J. M.

1982-01-01

The infrared astronomical data base and its principal data product, the catalog of Infrared Observations (CIO), comprise a machine readable library of infrared (1 microns to 1000 microns astronomical observations. To date, over 1300 journal articles and 10 major survey catalogs are included in this data base, which contains about 55,000 individual observations of about 10,000 different infrared sources. Of these, some 8,000 sources are identifiable with visible objects, and about 2,000 do not have known visible counterparts.

Identifying Learning Preferences in Vocational Education and Training Classroom Settings

ERIC Educational Resources Information Center

Smith, Peter J.

2006-01-01

This research was designed to assess whether teachers and trainers of vocational learners noted and valued differences in individual learning preferences and, if so, how those differences were observed in natural classroom, workshop or other formal learning settings. Data were collected from six vocational education and training (VET) learning…

Children's Temperaments and Their Relation to Behaviour and Emotion across Different Contexts.

ERIC Educational Resources Information Center

Kean, June

This observational study investigated children's temperaments and their relation to behavior and emotion across different contexts. Temperament, or individual behavioral style, was conceptualized as the manifestation of affect displays and social behaviors in context, with emotions acting as signals for interactions. Ratings of child temperament…

Learned Helplessness in High School Students Following Experience of Noncontingent Rewards.

ERIC Educational Resources Information Center

Buys, Nicholas J.; Winefield, Anthony H.

1982-01-01

Compared high-school students differing in achievement motivation in a learned helplessness experiment. A strong helplessness effect was observed in both high- and low-achievement motivation groups. Results show a strong learned helplessness effect unrelated to individual differences in achievement motivation and refute claims that helplessness…

Combined effect of Lactobacillus acidophilus and β-cyclodextrin on serum cholesterol in pigs.

PubMed

Alonso, L; Fontecha, J; Cuesta, P

2016-01-14

A total of twenty-four Yorkshire gilt pigs of 6-7 weeks of age were used in a 2×2 factorial experiment to determine the individual and combined effects of the inclusion of two dietary factors (cholesterol rich, 3% β-cyclodextrin (BCD) and Lactobacillus acidophilus cultures) on total cholesterol and LDL-cholesterol levels in blood serum. Pigs were assigned randomly to treatment groups (n 6). Total serum cholesterol concentrations decreased after 3 weeks in all the experimental treatment groups, including diets with BCD, L. acidophilus or both. Similar trends were observed for serum LDL-cholesterol concentrations among the experimental treatments. No statistically significant differences from the control group were observed in either total serum cholesterol or LDL-cholesterol concentrations (P<0·05) for each of the individual treatment groups: BCD or L. acidophilus. However, significant differences in total serum cholesterol concentrations were observed when comparing the combined treatment group (BCD and L. acidophilus) with the control group, which consisted of a basal diet and sterile milk. The combined treatment group exhibited 17·9% lower total serum cholesterol concentration after 3 weeks. Similar significant differences were observed when comparing the combined effect experimental group with the control group after 3 weeks. The combined treatment group exhibited 27·9% lower serum LDL-cholesterol concentrations.

Effects of personalized colorectal cancer risk information on laypersons' interest in colorectal cancer screening: The importance of individual differences.

PubMed

Han, Paul K J; Duarte, Christine W; Daggett, Susannah; Siewers, Andrea; Killam, Bill; Smith, Kahsi A; Freedman, Andrew N

2015-10-01

To evaluate how personalized quantitative colorectal cancer (CRC) risk information affects laypersons' interest in CRC screening, and to explore factors influencing these effects. An online pre-post experiment was conducted in which a convenience sample (N=578) of laypersons, aged >50, were provided quantitative personalized estimates of lifetime CRC risk, calculated by the National Cancer Institute Colorectal Cancer Risk Assessment Tool (CCRAT). Self-reported interest in CRC screening was measured immediately before and after CCRAT use; sociodemographic characteristics and prior CRC screening history were also assessed. Multivariable analyses assessed participants' change in interest in screening, and subgroup differences in this change. Personalized CRC risk information had no overall effect on CRC screening interest, but significant subgroup differences were observed. Change in screening interest was greater among individuals with recent screening (p=.015), higher model-estimated cancer risk (p=.0002), and lower baseline interest (p<.0001), with individuals at highest baseline interest demonstrating negative (not neutral) change in interest. Effects of quantitative personalized CRC risk information on laypersons' interest in CRC screening differ among individuals depending on prior screening history, estimated cancer risk, and baseline screening interest. Personalized cancer risk information has personalized effects-increasing and decreasing screening interest in different individuals. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Individual Differences in Discriminatory Fear Learning under Conditions of Ambiguity: A Vulnerability Factor for Anxiety Disorders?

PubMed Central

Arnaudova, Inna; Krypotos, Angelos-Miltiadis; Effting, Marieke; Boddez, Yannick; Kindt, Merel; Beckers, Tom

2013-01-01

Complex fear learning procedures might be better suited than the common differential fear-conditioning paradigm for detecting individual differences related to vulnerability for anxiety disorders. Two such procedures are the blocking procedure and the protection-from-overshadowing procedure. Their comparison allows for the examination of discriminatory fear learning under conditions of ambiguity. The present study examined the role of individual differences in such discriminatory fear learning. We hypothesized that heightened trait anxiety would be related to a deficit in discriminatory fear learning. Participants gave US-expectancy ratings as an index for the threat value of individual CSs following blocking and protection-from-overshadowing training. The difference in threat value at test between the protected-from-overshadowing conditioned stimulus (CS) and the blocked CS was negatively correlated with scores on a self-report tension-stress scale that approximates facets of generalized anxiety disorder (GAD), the Depression Anxiety Stress Scale-Stress (DASS-S), but not with other individual difference variables. In addition, a behavioral test showed that only participants scoring high on the DASS-S avoided the protected-from-overshadowing CS. This observed deficit in discriminatory fear learning for participants with high levels of tension-stress might be an underlying mechanism for fear overgeneralization in diffuse anxiety disorders such as GAD. PMID:23755030

Inter-observer variability in diagnosing radiological features of aneurysmal subarachnoid hemorrhage; a preliminary single centre study comparing observers from different specialties and levels of training.

PubMed

Siddiqui, Usman T; Khan, Anjum F; Shamim, Muhammad Shahzad; Hamid, Rana Shoaib; Alam, Muhammad Mehboob; Emaduddin, Muhammad

2014-01-01

A noncontrast computed tomography (CT) scan remains the initial radiological investigation of choice for a patient with suspected aneurysmal subarachnoid hemorrhage (aSAH). This initial scan may be used to derive key information about the underlying aneurysm which may aid in further management. The interpretation, however, is subject to the skill and experience of the interpreting individual. The authors here evaluate the interpretation of such CT scans by different individuals at different levels of training, and in two different specialties (Radiology and Neurosurgery). Initial nonontrast CT scan of 35 patients with aSAH was evaluated independently by four different observers. The observers selected for the study included two from Radiology and two from Neurosurgery at different levels of training; a resident currently in mid training and a resident who had recently graduated from training of each specialty. Measured variables included interpreter's suspicion of presence of subarachnoid blood, side of the subarachnoid hemorrhage, location of the aneurysm, the aneurysm's proximity to vessel bifurcation, number of aneurysm(s), contour of aneurysm(s), presence of intraventricular hemorrhage (IVH), intracerebral hemorrhage (ICH), infarction, hydrocephalus and midline shift. To determine the inter-observer variability (IOV), weighted kappa values were calculated. There was moderate agreement on most of the CT scan findings among all observers. Substantial agreement was found amongst all observers for hydrocephalus, IVH, and ICH. Lowest agreement rates were seen in the location of aneurysm being supra or infra tentorial. There were, however, some noteworthy exceptions. There was substantial to almost perfect agreement between the radiology graduate and radiology resident on most CT findings. The lowest agreement was found between the neurosurgery graduate and the radiology graduate. Our study suggests that although agreements were seen in the interpretation of some of the radiological features of aSAH, there is still considerable IOV in the interpretation of most features among physicians belonging to different levels of training and different specialties. Whether these might affect management or outcome is unclear.

Ethnic differences in progression of islet autoimmunity and type 1 diabetes in relatives at risk.

PubMed

Tosur, Mustafa; Geyer, Susan M; Rodriguez, Henry; Libman, Ingrid; Baidal, David A; Redondo, Maria J

2018-06-21

We hypothesised that progression of islet autoimmunity and type 1 diabetes mellitus differs among races/ethnicities in at-risk individuals. In this study, we analysed the data from the Type 1 Diabetes TrialNet Pathway to Prevention Study. We studied 4873 non-diabetic, autoantibody-positive relatives of individuals with type 1 diabetes followed prospectively (11% Hispanic, 80.9% non-Hispanic white [NHW], 2.9% non-Hispanic black [NHB] and 5.2% non-Hispanic other [NHO]). Primary outcomes were time from single autoantibody positivity confirmation to multiple autoantibody positivity, and time from multiple autoantibody positivity to type 1 diabetes mellitus diagnosis. Conversion from single to multiple autoantibody positivity was less common in Hispanic individuals than in NHW individuals (HR 0.66 [95% CI 0.46, 0.96], p = 0.028) adjusting for autoantibody type, age, sex, Diabetes Prevention Trial Type 1 Risk Score and HLA-DR3-DQ2/DR4-DQ8 genotype. In participants who screened positive for multiple autoantibodies (n = 2834), time to type 1 diabetes did not differ by race/ethnicity overall (p = 0.91). In children who were <12 years old when multiple autoantibody positivity was determined, being overweight/obese had differential effects by ethnicity: type 1 diabetes risk was increased by 36% in NHW children (HR 1.36 [95% CI 1.04, 1.77], p = 0.024) and was nearly quadrupled in Hispanic children (HR 3.8 [95% CI 1.6, 9.1], p = 0.0026). We did not observe this interaction in participants who were ≥12 years old at determination of autoantibody positivity, although this group size was limited. No significant differential risks were observed between individuals of NHB and NHW ethnicity. The risk and rate of progression of islet autoimmunity were lower in Hispanic compared with NHW at-risk individuals, while significant differences in the development of type 1 diabetes were limited to children <12 years old and were modified by BMI.

The Interaction of Ethanol Ingestion and Social Interaction with an Intoxicated Peer on the Odor-Mediated Response to the Drug in Adolescent Rats.

PubMed

Eade, Amber M; Youngentob, Lisa M; Youngentob, Steven L

2016-04-01

Using a social transmission of food preference paradigm in rats, we previously demonstrated that ethanol (EtOH) exposure during adolescence, as either an observer (interaction with an intoxicated conspecific) or demonstrator (intragastric infusion with EtOH), altered the reflexive odor-mediated responses to the drug. The 2 modes of exposure were equivalent in the magnitude of their effects. Human adolescents, however, are likely to experience the drug in a social setting as both an EtOH observer and demonstrator. That is, both interacting with an intoxicated peer and experiencing EtOH's postingestive consequences in conjunction with hematogenic olfaction. Therefore, we tested whether combined adolescent exposure as both an observer and demonstrator differed from either form of individual experience. Beginning on postnatal day (P) 29, naïve rats received EtOH or water exposures in a social interaction paradigm as either an observer, a demonstrator, or combined experience (where each animal in the interaction was, itself, an observer and demonstrator). Exposures occurred 4 times, once every 48 hours. On P37, the reflexive behavioral response to EtOH odor was tested, using whole-body plethysmography. The odor-mediated responses of adolescent EtOH observers, demonstrators, and combined exposure animals all significantly differed from controls. Compared to controls, however, the magnitude of the behavioral effect was greatest in the combined exposure animals. Moreover, combined exposure as both an EtOH observer and demonstrator significantly differed from either form of individual EtOH experience. EtOH's component chemosensory qualities are known to be central contributors to its acceptance and increases in the acceptability of EtOH's odor, resulting from a social transmission experience, are predictive of enhanced EtOH avidity in adolescence. Our findings demonstrate that combined exposure as an observer and demonstrator, within a socially relevant framework, may represent a higher risk scenario for increased EtOH avidity in adolescence (and by extension adult persistence) as compared to the individual effects of direct ingestion or social experience with the drug. Copyright © 2016 by the Research Society on Alcoholism.

Testing the effects of expression, intensity and age on emotional face processing in ASD.

PubMed

Luyster, Rhiannon J; Bick, Johanna; Westerlund, Alissa; Nelson, Charles A

2017-06-21

Individuals with autism spectrum disorder (ASD) commonly show global deficits in the processing of facial emotion, including impairments in emotion recognition and slowed processing of emotional faces. Growing evidence has suggested that these challenges may increase with age, perhaps due to minimal improvement with age in individuals with ASD. In the present study, we explored the role of age, emotion type and emotion intensity in face processing for individuals with and without ASD. Twelve- and 18-22- year-old children with and without ASD participated. No significant diagnostic group differences were observed on behavioral measures of emotion processing for younger versus older individuals with and without ASD. However, there were significant group differences in neural responses to emotional faces. Relative to TD, at 12 years of age and during adulthood, individuals with ASD showed slower N170 to emotional faces. While the TD groups' P1 latency was significantly shorter in adults when compared to 12 year olds, there was no significant age-related difference in P1 latency among individuals with ASD. Findings point to potential differences in the maturation of cortical networks that support visual processing (whether of faces or stimuli more broadly), among individuals with and without ASD between late childhood and adulthood. Finally, associations between ERP amplitudes and behavioral responses on emotion processing tasks suggest possible neural markers for emotional and behavioral deficits among individuals with ASD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Health and work in the family: Evidence from spouses' cancer diagnoses.

PubMed

Jeon, Sung-Hee; Pohl, R Vincent

2017-03-01

Using Canadian administrative data from multiple sources, we provide the first nationally representative estimates for the effect of spouses' cancer diagnoses on individuals' employment and earnings and on family income. Our identification strategy exploits unexpected health shocks and combines matching with individual fixed effects in a generalized difference-in-differences framework to control for observable and unobservable heterogeneity. While the effect of spousal health shocks on labor supply is theoretically ambiguous, we find strong evidence for a decline in employment and earnings of individuals whose spouses are diagnosed with cancer. We interpret this result as individuals reducing their labor supply to provide care to their sick spouses and to enjoy joint leisure. Family income substantially declines after spouses' cancer diagnoses, suggesting that the financial consequences of such health shocks are considerable. Copyright © 2017 Elsevier B.V. All rights reserved.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People.

PubMed

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people.

No Sensory Compensation for Olfactory Memory: Differences between Blind and Sighted People

PubMed Central

Sorokowska, Agnieszka; Karwowski, Maciej

2017-01-01

Blindness can be a driving force behind a variety of changes in sensory systems. When vision is missing, other modalities and higher cognitive functions can become hyper-developed through a mechanism called sensory compensation. Overall, previous studies suggest that olfactory memory in blind people can be better than that of the sighted individuals. Better performance of blind individuals in other-sensory modalities was hypothesized to be a result of, among others, intense perceptual training. At the same time, if the superiority of blind people in olfactory abilities indeed results from training, their scores should not decrease with age to such an extent as among the sighted people. Here, this hypothesis was tested in a large sample of 94 blind individuals. Olfactory memory was assessed using the Test for Olfactory Memory, comprising episodic odor recognition (discriminating previously presented odors from new odors) and two forms of semantic memory (cued and free identification of odors). Regarding episodic olfactory memory, we observed an age-related decline in correct hits in blind participants, but an age-related increase in false alarms in sighted participants. Further, age moderated the between-group differences for correct hits, but the direction of the observed effect was contrary to our expectations. The difference between blind and sighted individuals younger than 40 years old was non-significant, but older sighted individuals outperformed their blind counterparts. In conclusion, we found no positive effect of visual impairment on olfactory memory. We suggest that daily perceptual training is not enough to increase olfactory memory function in blind people. PMID:29276494

Facial Cosmetics and Attractiveness: Comparing the Effect Sizes of Professionally-Applied Cosmetics and Identity.

PubMed

Jones, Alex L; Kramer, Robin S S

2016-01-01

Forms of body decoration exist in all human cultures. However, in Western societies, women are more likely to engage in appearance modification, especially through the use of facial cosmetics. How effective are cosmetics at altering attractiveness? Previous research has hinted that the effect is not large, especially when compared to the variation in attractiveness observed between individuals due to differences in identity. In order to build a fuller understanding of how cosmetics and identity affect attractiveness, here we examine how professionally-applied cosmetics alter attractiveness and compare this effect with the variation in attractiveness observed between individuals. In Study 1, 33 YouTube models were rated for attractiveness before and after the application of professionally-applied cosmetics. Cosmetics explained a larger proportion of the variation in attractiveness compared with previous studies, but this effect remained smaller than variation caused by differences in attractiveness between individuals. Study 2 replicated the results of the first study with a sample of 45 supermodels, with the aim of examining the effect of cosmetics in a sample of faces with low variation in attractiveness between individuals. While the effect size of cosmetics was generally large, between-person variability due to identity remained larger. Both studies also found interactions between cosmetics and identity-more attractive models received smaller increases when cosmetics were worn. Overall, we show that professionally-applied cosmetics produce a larger effect than self-applied cosmetics, an important theoretical consideration for the field. However, the effect of individual differences in facial appearance is ultimately more important in perceptions of attractiveness.

Facial Cosmetics and Attractiveness: Comparing the Effect Sizes of Professionally-Applied Cosmetics and Identity

PubMed Central

Kramer, Robin S. S.

2016-01-01

Forms of body decoration exist in all human cultures. However, in Western societies, women are more likely to engage in appearance modification, especially through the use of facial cosmetics. How effective are cosmetics at altering attractiveness? Previous research has hinted that the effect is not large, especially when compared to the variation in attractiveness observed between individuals due to differences in identity. In order to build a fuller understanding of how cosmetics and identity affect attractiveness, here we examine how professionally-applied cosmetics alter attractiveness and compare this effect with the variation in attractiveness observed between individuals. In Study 1, 33 YouTube models were rated for attractiveness before and after the application of professionally-applied cosmetics. Cosmetics explained a larger proportion of the variation in attractiveness compared with previous studies, but this effect remained smaller than variation caused by differences in attractiveness between individuals. Study 2 replicated the results of the first study with a sample of 45 supermodels, with the aim of examining the effect of cosmetics in a sample of faces with low variation in attractiveness between individuals. While the effect size of cosmetics was generally large, between-person variability due to identity remained larger. Both studies also found interactions between cosmetics and identity–more attractive models received smaller increases when cosmetics were worn. Overall, we show that professionally-applied cosmetics produce a larger effect than self-applied cosmetics, an important theoretical consideration for the field. However, the effect of individual differences in facial appearance is ultimately more important in perceptions of attractiveness. PMID:27727311

Two cases of mother-infant cannibalism in orangutans.

PubMed

Dellatore, David Fenwick; Waitt, Corri D; Foitova, Ivona

2009-07-01

Observations of ape cannibalism have to this point been limited to chimpanzees (Pan troglodytes) where it is associated with infanticide and consumption by unrelated individuals (Watts and Mitani, Primates 41(4):357-365, 2000). Here we report for the first time observations of two unrelated female Sumatran orangutans (Pongo abelii) cannibalizing the remains of their infants on different occasion, a behavior never before reported in any ape species. The two orangutans were wild-born rehabilitated individuals, and had been reintroduced to an area hosting a largely unregulated primate tourism industry and experienced restricted ranging conditions. Though it is possible that this is a strategy to regain energy and nutrients or a result of individual history, comparative data suggest that this is an aberrant behavior which may be linked to environmental stressors within the area.

Inferring individual-level processes from population-level patterns in cultural evolution.

PubMed

Kandler, Anne; Wilder, Bryan; Fortunato, Laura

2017-09-01

Our species is characterized by a great degree of cultural variation, both within and between populations. Understanding how group-level patterns of culture emerge from individual-level behaviour is a long-standing question in the biological and social sciences. We develop a simulation model capturing demographic and cultural dynamics relevant to human cultural evolution, focusing on the interface between population-level patterns and individual-level processes. The model tracks the distribution of variants of cultural traits across individuals in a population over time, conditioned on different pathways for the transmission of information between individuals. From these data, we obtain theoretical expectations for a range of statistics commonly used to capture population-level characteristics (e.g. the degree of cultural diversity). Consistent with previous theoretical work, our results show that the patterns observed at the level of groups are rooted in the interplay between the transmission pathways and the age structure of the population. We also explore whether, and under what conditions, the different pathways can be distinguished based on their group-level signatures, in an effort to establish theoretical limits to inference. Our results show that the temporal dynamic of cultural change over time retains a stronger signature than the cultural composition of the population at a specific point in time. Overall, the results suggest a shift in focus from identifying the one individual-level process that likely produced the observed data to excluding those that likely did not. We conclude by discussing the implications for empirical studies of human cultural evolution.

Inter-individual Variability in Soccer Players of Different Age Groups Playing Different Positions

PubMed Central

Nikolaidis, Pantelis; Ziv, Gal; Lidor, Ronnie; Arnon, Michal

2014-01-01

The purpose of this study was twofold: (a) to profile physical characteristics and motor abilities of three age groups of soccer players – under 14 years, 14–17, and over 17, playing different positions – goalkeepers, defenders, midfielders, and forwards; and (b) to examine the inter-individual variability among the players in each age group in all physical and physiological measurements performed in the study. In addition, anthropometric, power, strength, and flexibility tests were administered. Findings showed large inter-individual variability in all three age groups and in all playing positions. Differences between playing positions were found only in the 14–17 group (body mass) and in the over-17 group (body height, body mass, fat-free mass, and mean power in the Wingate Anaerobic Test). Due to the observed large inter-individual variability, it was concluded that the findings obtained in the physical and physiological tests should be interpreted with caution when attempting to differentiate between successful and unsuccessful soccer players, as well as when trying to predict future success in soccer. PMID:25031689

Immunoprecipitation of human immunodeficiency virus type 2 glycoproteins by sera positive for human immunodeficiency virus type 1.

PubMed Central

Espejo, R T; Uribe, P

1990-01-01

Analysis by radioimmunoprecipitation of serum samples from 27 different human immunodeficiency virus type 1 (HIV-1)-infected individuals residing in Chile showed that the sera of 26% of these individuals also react with glycoprotein gp125 of HIV type 2 (HIV-2). This cross-reaction seems to reflect a qualitative difference among infected individuals, because the titer of antibodies against gp120 of HIV-1 in the cross-reacting samples did not differ significantly from that in the non-cross-reacting samples. Most of the HIV-1-seropositive sera, including many that did not react with gp125 of HIV-2, reacted with gp140, the precursor of HIV-2 glycoproteins. The observed cross-reactions allowed us to distinguish three groups of HIV-1-infected individuals: (i) those whose sera react with both gp140 and gp125, (ii) those whose sera react with gp140, and (iii) those whose sera react with neither of these glycoproteins. The possible cause and significance of these differences is under study. Images PMID:2229392

Simple model of epidemics with pathogen mutation.

PubMed

Girvan, Michelle; Callaway, Duncan S; Newman, M E J; Strogatz, Steven H

2002-03-01

We study how the interplay between the memory immune response and pathogen mutation affects epidemic dynamics in two related models. The first explicitly models pathogen mutation and individual memory immune responses, with contacted individuals becoming infected only if they are exposed to strains that are significantly different from other strains in their memory repertoire. The second model is a reduction of the first to a system of difference equations. In this case, individuals spend a fixed amount of time in a generalized immune class. In both models, we observe four fundamentally different types of behavior, depending on parameters: (1) pathogen extinction due to lack of contact between individuals; (2) endemic infection; (3) periodic epidemic outbreaks; and (4) one or more outbreaks followed by extinction of the epidemic due to extremely low minima in the oscillations. We analyze both models to determine the location of each transition. Our main result is that pathogens in highly connected populations must mutate rapidly in order to remain viable.

Hyperactives as young adults: preliminary report.

PubMed Central

Hechtman, L.; Weiss, G.; Finklestein, J.; Werner, A.; Benn, R.

1976-01-01

Thirty-five individuals aged 17 to 24 in whom severe chronic hyperactivity had been diagnosed 10 years before were studied together with 25 matched controls. There were no significant differences in mean height or weight or in electroencephalographic findings, but the mean pulse rate was significantly higher in the hyperactive group. Cognitive style tests indicated continued difficulty in reflection (resulting in more errors) but less impulsivity (longer reaction time) in the hyperactive individuals. Compared with controls, hyperactive subjects were continuing to have more scholastic difficulty, although this difference seemed to be less pronounced than 5 years before. Their adjustment in work situations and living arrangements did not differ significantly from that of the controls. Restlessness, both reported and observed, continued to be a problem for the hyperactive individuals, and socialization skills and sense of well-being continued to be poorer than in the controls. The hyperactive individuals did not show significantly more antisocial behaviour, nonmedical use of drugs or serious psychiatric disturbances. PMID:974949

Hyperactives as young adults: preliminary report.

PubMed

Hechtman, L; Weiss, G; Finklestein, J; Werner, A; Benn, R

1976-10-09

Thirty-five individuals aged 17 to 24 in whom severe chronic hyperactivity had been diagnosed 10 years before were studied together with 25 matched controls. There were no significant differences in mean height or weight or in electroencephalographic findings, but the mean pulse rate was significantly higher in the hyperactive group. Cognitive style tests indicated continued difficulty in reflection (resulting in more errors) but less impulsivity (longer reaction time) in the hyperactive individuals. Compared with controls, hyperactive subjects were continuing to have more scholastic difficulty, although this difference seemed to be less pronounced than 5 years before. Their adjustment in work situations and living arrangements did not differ significantly from that of the controls. Restlessness, both reported and observed, continued to be a problem for the hyperactive individuals, and socialization skills and sense of well-being continued to be poorer than in the controls. The hyperactive individuals did not show significantly more antisocial behaviour, nonmedical use of drugs or serious psychiatric disturbances.

Screening NK-, B- and T-cell phenotype and function in patients suffering from Chronic Fatigue Syndrome.

PubMed

Curriu, Marta; Carrillo, Jorge; Massanella, Marta; Rigau, Josepa; Alegre, José; Puig, Jordi; Garcia-Quintana, Ana M; Castro-Marrero, Jesus; Negredo, Eugènia; Clotet, Bonaventura; Cabrera, Cecilia; Blanco, Julià

2013-03-20

Chronic Fatigue Syndrome (CFS) is a debilitating neuro-immune disorder of unknown etiology diagnosed by an array of clinical manifestations. Although several immunological abnormalities have been described in CFS, their heterogeneity has limited diagnostic applicability. Immunological features of CFS were screened in 22 CFS diagnosed individuals fulfilling Fukuda criteria and 30 control healthy individuals. Peripheral blood T, B and NK cell function and phenotype were analyzed by flow cytometry in both groups. CFS diagnosed individuals showed similar absolute numbers of T, B and NK cells, with minor differences in the percentage of CD4+ and CD8+ T cells. B cells showed similar subset frequencies and proliferative responses between groups. Conversely, significant differences were observed in T cell subsets. CFS individuals showed increased levels of T regulatory cells (CD25+/FOXP3+) CD4 T cells, and lower proliferative responses in vitro and in vivo. Moreover, CD8 T cells from the CFS group showed significantly lower activation and frequency of effector memory cells. No clear signs of T-cell immunosenescence were observed. NK cells from CFS individuals displayed higher expression of NKp46 and CD69 but lower expression of CD25 in all NK subsets defined. Overall, T cell and NK cell features clearly clustered CFS individuals. Our findings suggest that alterations in T-cell phenotype and proliferative response along with the specific signature of NK cell phenotype may be useful to identify CFS individuals. The striking down modulation of T cell mediated immunity may help to understand intercurrent viral infections in CFS.

Screening NK-, B- and T-cell phenotype and function in patients suffering from Chronic Fatigue Syndrome

PubMed Central

2013-01-01

Background Chronic Fatigue Syndrome (CFS) is a debilitating neuro-immune disorder of unknown etiology diagnosed by an array of clinical manifestations. Although several immunological abnormalities have been described in CFS, their heterogeneity has limited diagnostic applicability. Methods Immunological features of CFS were screened in 22 CFS diagnosed individuals fulfilling Fukuda criteria and 30 control healthy individuals. Peripheral blood T, B and NK cell function and phenotype were analyzed by flow cytometry in both groups. Results CFS diagnosed individuals showed similar absolute numbers of T, B and NK cells, with minor differences in the percentage of CD4+ and CD8+ T cells. B cells showed similar subset frequencies and proliferative responses between groups. Conversely, significant differences were observed in T cell subsets. CFS individuals showed increased levels of T regulatory cells (CD25+/FOXP3+) CD4 T cells, and lower proliferative responses in vitro and in vivo. Moreover, CD8 T cells from the CFS group showed significantly lower activation and frequency of effector memory cells. No clear signs of T-cell immunosenescence were observed. NK cells from CFS individuals displayed higher expression of NKp46 and CD69 but lower expression of CD25 in all NK subsets defined. Overall, T cell and NK cell features clearly clustered CFS individuals. Conclusions Our findings suggest that alterations in T-cell phenotype and proliferative response along with the specific signature of NK cell phenotype may be useful to identify CFS individuals. The striking down modulation of T cell mediated immunity may help to understand intercurrent viral infections in CFS. PMID:23514202

Dispersal and individual quality in a long lived species

USGS Publications Warehouse

Cam, E.; Monnat, J.-Y.; Royle, J. Andrew

2004-01-01

The idea of differences in individual quality has been put forward in numerous long-term studies in long-lived species to explain differences in lifetime production among individuals. Despite the important role of individual heterogeneity in vital rates in demography, population dynamics and life history theory, the idea of 'individual quality' is elusive. It is sometimes assumed to be a static or dynamic individual characteristic. When considered as a dynamic trait, it is sometimes assumed to vary deterministically or stochastically, or to be confounded with the characteristics of the habitat. We addressed heterogeneity in reproductive performance among individuals established in higher-quality habitat in a long-lived seabird species. We used approaches to statistical inference based on individual random effects permitting quantification of heterogeneity in populations and assessment of individual variation from the population mean. We found evidence of heterogeneity in breeding probability, not success probability. We assessed the influence of dispersal on individual reproductive potential. Dispersal is likely to be destabilizing in species with high site and mate fidelity. We detected heterogeneity after dispersal, not before. Individuals may perform well regardless of quality before destabilization, including those that recruited in higher-quality habitat by chance, but only higher-quality individuals may be able to overcome the consequences of dispersal. Importantly, results differed when accounting for individual heterogeneity (an increase in mean breeding probability when individuals dispersed), or not (a decrease in mean breeding probability). In the latter case, the decrease in mean breeding probability may result from a substantial decrease in breeding probability in a few individuals and a slight increase in others. In other words, the pattern observed at the population mean level may not reflect what happens in the majority of individuals.

Serum and plasma brain-derived neurotrophic factor (BDNF) in abstinent alcoholics and social drinkers

PubMed Central

D’Sa, Carrol; Dileone, Ralph J.; Anderson, George M.; Sinha, Rajita

2013-01-01

Although the effects of alcohol on brain-derived neurotrophic factor (BDNF) have been extensively studied in rodents, BDNF levels have rarely been measured in abstinent, alcohol-dependent (AD) individuals. Interpretation of reported group comparisons of serum BDNF levels is difficult due to limited information regarding analytical variance, biological variability, and the relative contribution of platelet and plasma pools to serum BDNF. Analytical variance (intra- and inter-assay coefficients of variation) of the enzyme-linked immunosorbent assay (ELISA) was characterized. Within- and between-subject variability, and group differences in serum and plasma BDNF, was assessed on three separate days in 16, 4-week abstinent AD individuals (7M/9F) and 16 social drinkers (SDs; 8M/8F). Significantly higher mean (±sd) serum BDNF levels were observed for the AD group compared to the SD (p = 0.003). No significant difference in mean baseline plasma BDNF levels was observed between AD and SD groups. The low analytical variance, high day-to-day within-individual stability and the high degree of individuality demonstrates the potential clinical utility of measuring serum BDNF levels. The low correlations that we observed between plasma and serum levels are congruent with their representing separate pools of BDNF. The observation of higher basal serum BDNF in the AD group without a concomitant elevation in plasma BDNF levels indicates that the elevated serum BDNF in AD patients is not due to greater BDNF exposure. Further research is warranted to fully elucidate mechanisms underlying this alteration and determine the utility of serum BDNF as a predictor or surrogate marker of chronic alcohol abuse. PMID:22364688

Do Visually Impaired People Develop Superior Smell Ability?

PubMed

Majchrzak, Dorota; Eberhard, Julia; Kalaus, Barbara; Wagner, Karl-Heinz

2017-10-01

It is well known that visually impaired people perform better in orientation by sound than sighted individuals, but it is not clear whether this enhanced awareness also extends to other senses. Therefore, the aim of this study was to observe whether visually impaired subjects develop superior abilities in olfactory perception to compensate for their lack of vision. We investigated the odor perception of visually impaired individuals aged 7 to 89 ( n = 99; 52 women, 47 men) and compared them with subjects of a control group aged 8 to 82 years ( n = 100; 45 women, 55 men) without any visual impairment. The participants were evaluated by Sniffin' Sticks odor identification and discrimination test. Identification ability was assessed for 16 common odors presented in felt-tip pens. In the odor discrimination task, subjects had to determine which of three pens in 16 triplets had a different odor. The median number of correctly identified odorant pens in both groups was the same, 13 of the offered 16. In the discrimination test, there was also no significant difference observed. Gender did not influence results. Age-related changes were observed in both groups with olfactory perception decreasing after the age of 51. We could not confirm that visually impaired people were better in smell identification and discrimination ability than sighted individuals.

Low back pain prevalence in healthcare professionals and identification of factors affecting low back pain.

PubMed

Çınar-Medeni, Özge; Elbasan, Bulent; Duzgun, Irem

2017-01-01

Work-related musculoskeletal system diseases are commonly observed among nurses, physiotherapists, dentists, and dieticians. To assess working postures of nurses, physiotherapists, dentists and dieticians, to identify whether low back pain (LBP) is present, and to put forth the correlation between LBP, working posture, and other factors. Twenty seven physiotherapists, 34 nurses, 30 dentists, and 16 dieticians were included. Impairment ratings of cases with LBP were analysed with Quebec Back Pain Disability Scale (Quebec). Working postures were analysed with Owako Working Posture Analysis System. LBP was observed in 70.09% of healthcare professionals. Of the individuals suffering from LBP, 57.2% were working with a risky posture. 40.63% of individuals without LBP were using risky working postures. Trunk and head posture distribution of individuals with and without LBP was found as different from each other (p < 0.05). LBP prevalence of dentists and nurses were higher compared to other groups (p < 0.05). Quebec scores of professionals with LBP were not different among occupations (p > 0.05). Quebec scores were observed as correlated with various factors in various occupation groups. Considering that head-neck and trunk postures are changeable factors that are among the factors affecting LBP, correcting the working posture gains importance.

Behavioral and TMS Markers of Action Observation Might Reflect Distinct Neuronal Processes.

PubMed

Hétu, Sébastien; Taschereau-Dumouchel, Vincent; Meziane, Hadj Boumediene; Jackson, Philip L; Mercier, Catherine

2016-01-01

Transcranial magnetic stimulation (TMS) studies have shown that observing an action induces muscle-specific changes in corticospinal excitability. From a signal detection theory standpoint, this pattern can be related to sensitivity, which here would measure the capacity to distinguish between two action observation conditions. In parallel to these TMS studies, action observation has also been linked to behavioral effects such as motor priming and interference. It has been hypothesized that behavioral markers of action observation could be related to TMS markers and thus represent a potentially cost-effective mean of assessing the functioning of the action-perception system. However, very few studies have looked at possible relationships between these two measures. The aim of this study was to investigate if individual differences in sensitivity to action observation could be related to the behavioral motor priming and interference effects produced by action observation. To this end, 14 healthy participants observed index and little finger movements during a TMS task and a stimulus-response compatibility task. Index muscle displayed sensitivity to action observation, and action observation resulted in significant motor priming+interference, while no significant effect was observed for the little finger in both task. Nevertheless, our results indicate that the sensitivity measured in TMS was not related to the behavioral changes measured in the stimulus-response compatibility task. Contrary to a widespread assumption, the current results indicate that individual differences in physiological and behavioral markers of action observation may be unrelated. This could have important impacts on the potential use of behavioral markers in place of more costly physiological markers of action observation in clinical settings.

Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use.

PubMed

Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R

2013-01-01

Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior.

Differential mesolimbic and prefrontal alterations during reward anticipation and consummation in positive and negative schizotypy.

PubMed

Yan, Chao; Wang, Yi; Su, Li; Xu, Ting; Yin, Da-Zhi; Fan, Ming-Xia; Deng, Ci-Ping; Wang, Zhao-Xin; Lui, Simon S Y; Cheung, Eric F C; Chan, Raymond C K

2016-08-30

Schizotypy is associated with anhedonia. However, previous findings on the neural substrates of anhedonia in schizotypy are mixed. In the present study, we measured the neural substrates associated with reward anticipation and consummation in positive and negative schizotypy using functional MRI. The Monetary Incentive Delay task was administered to 33 individuals with schizotypy (18 positive schizotypy (PS),15 negative schizotypy (NS)) and 22 healthy controls. Comparison between schizotypy individuals and controls were performed using two-sample T tests for contrast images involving gain versus non-gain anticipation condition and gain versus non-gain consummation condition. Multiple comparisons were corrected using Monte Carlo Simulation correction of p<.05. The results showed no significant difference in brain activity between controls and schizotypy individuals as a whole during gain anticipation or consummation. However, during the consummatory phase, NS individuals rather than PS individuals showed diminished left amygdala and left putamen activity compared with controls. We observed significantly weaker activation at the left ventral striatum during gain anticipation in NS individuals compared with controls. PS individuals, however, exhibited enhanced right ventral lateral prefrontal activity. These findings suggest that different dimensions of schizotypy may be underlied by different neural dysfunctions in reward anticipation and consummation. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Differences in mobility at the range edge of an expanding invasive population of Xenopus laevis in the west of France.

PubMed

Louppe, Vivien; Courant, Julien; Herrel, Anthony

2017-01-15

Theoretical models predict that spatial sorting at the range edge of expanding populations should favor individuals with increased mobility relative to individuals at the center of the range. Despite the fact that empirical evidence for the evolution of locomotor performance at the range edge is rare, data on cane toads support this model. However, whether this can be generalized to other species remains largely unknown. Here, we provide data on locomotor stamina and limb morphology in individuals from two sites: one from the center and one from the periphery of an expanding population of the clawed frog Xenopus laevis in France where it was introduced about 30 years ago. Additionally, we provide data on the morphology of frogs from two additional sites to test whether the observed differences can be generalized across the range of this species in France. Given the known sexual size dimorphism in this species, we also test for differences between the sexes in locomotor performance and morphology. Our results show significant sexual dimorphism in stamina and morphology, with males having longer legs and greater stamina than females. Moreover, in accordance with the predictions from theoretical models, individuals from the range edge had a greater stamina. This difference in locomotor performance is likely to be driven by the significantly longer limb segments observed in animals in both sites sampled in different areas along the range edge. Our data have implications for conservation because spatial sorting on the range edge may lead to an accelerated increase in the spread of this invasive species in France. © 2017. Published by The Company of Biologists Ltd.

Impact of Different Surgeons on Dental Implant Failure.

PubMed

Chrcanovic, Bruno Ramos; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

To assess the influence of several factors on the prevalence of dental implant failure, with special consideration of the placement of implants by different dental surgeons. This retrospective study is based on 2,670 patients who received 10,096 implants at one specialist clinic. Only the data of patients and implants treated by surgeons who had inserted a minimum of 200 implants at the clinic were included. Kaplan-Meier curves were stratified with respect to the individual surgeon. A generalized estimating equation (GEE) method was used to account for the fact that repeated observations (several implants) were placed in a single patient. The factors bone quantity, bone quality, implant location, implant surface, and implant system were analyzed with descriptive statistics separately for each individual surgeon. A total of 10 surgeons were eligible. The differences between the survival curves of each individual were statistically significant. The multivariate GEE model showed the following variables to be statistically significant: surgeon, bruxism, intake of antidepressants, location, implant length, and implant system. The surgeon with the highest absolute number of failures was also the one who inserted the most implants in sites of poor bone and used turned implants in most cases, whereas the surgeon with the lowest absolute number of failures used mainly modern implants. Separate survival analyses of turned and modern implants stratified for the individual surgeon showed statistically significant differences in cumulative survival. Different levels of failure incidence could be observed between the surgeons, occasionally reaching significant levels. Although a direct causal relationship could not be ascertained, the results of the present study suggest that the surgeons' technique, skills, and/or judgment may negatively influence implant survival rates.

Individual and institutional factors associated with functional disability in nursing home residents: An observational study with multilevel analysis.

PubMed

Serrano-Urrea, Ramón; Gómez-Rubio, Virgilio; Palacios-Ceña, Domingo; Fernández-de-Las-Peñas, César; García-Meseguer, María José

2017-01-01

High prevalence of functional limitations has been previously observed in nursing homes. Disability may depend not only on the characteristics of the residents but also on the facility characteristics. The aims of this study were: 1, to describe the prevalence of functional disability in older people living in Spanish nursing homes; and 2, to analyze the relationships between individual and nursing home characteristics and residents' functional disability. A cross-sectional study with data collected from 895 residents in 34 nursing homes in the province of Albacete (Spain) was conducted. Functional status was assessed by the Barthel Index. Taking into account both levels of data (individual and institutional characteristics) we resorted to a multilevel analysis in order to take different sources of variability in the data. The prevalence of functional disability of the total sample was 79.8%. The best fitting multilevel model showed that female gender, older age, negative self-perception of health, and living in private nursing homes were factors significantly associated with functional disability. After separating individual and institutional effects, the institutions showed significant differences. In line with previous findings, our study found high levels of functional dependence among institutionalized elders. Gender, age, self-perception of health, and institution ownership were associated with functional status. Disentangling individual and institutional effects by means of multilevel models can help evaluate the quality of the residences.

The nature of creativity: The roles of genetic factors, personality traits, cognitive abilities, and environmental sources.

PubMed

Kandler, Christian; Riemann, Rainer; Angleitner, Alois; Spinath, Frank M; Borkenau, Peter; Penke, Lars

2016-08-01

This multitrait multimethod twin study examined the structure and sources of individual differences in creativity. According to different theoretical and metrological perspectives, as well as suggestions based on previous research, we expected 2 aspects of individual differences, which can be described as perceived creativity and creative test performance. We hypothesized that perceived creativity, reflecting typical creative thinking and behavior, should be linked to specific personality traits, whereas test creativity, reflecting maximum task-related creative performance, should show specific associations with cognitive abilities. Moreover, we tested whether genetic variance in intelligence and personality traits account for the genetic component of creativity. Multiple-rater and multimethod data (self- and peer reports, observer ratings, and test scores) from 2 German twin studies-the Bielefeld Longitudinal Study of Adult Twins and the German Observational Study of Adult Twins-were analyzed. Confirmatory factor analyses yielded the expected 2 correlated aspects of creativity. Perceived creativity showed links to openness to experience and extraversion, whereas tested figural creativity was associated with intelligence and also with openness. Multivariate behavioral genetic analyses indicated that the heritability of tested figural creativity could be accounted for by the genetic component of intelligence and openness, whereas a substantial genetic component in perceived creativity could not be explained. A primary source of individual differences in creativity was due to environmental influences, even after controlling for random error and method variance. The findings are discussed in terms of the multifaceted nature and construct validity of creativity as an individual characteristic. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

Population genetic differentiation of height and body mass index across Europe.

PubMed

Robinson, Matthew R; Hemani, Gibran; Medina-Gomez, Carolina; Mezzavilla, Massimo; Esko, Tonu; Shakhbazov, Konstantin; Powell, Joseph E; Vinkhuyzen, Anna; Berndt, Sonja I; Gustafsson, Stefan; Justice, Anne E; Kahali, Bratati; Locke, Adam E; Pers, Tune H; Vedantam, Sailaja; Wood, Andrew R; van Rheenen, Wouter; Andreassen, Ole A; Gasparini, Paolo; Metspalu, Andres; Berg, Leonard H van den; Veldink, Jan H; Rivadeneira, Fernando; Werge, Thomas M; Abecasis, Goncalo R; Boomsma, Dorret I; Chasman, Daniel I; de Geus, Eco J C; Frayling, Timothy M; Hirschhorn, Joel N; Hottenga, Jouke Jan; Ingelsson, Erik; Loos, Ruth J F; Magnusson, Patrik K E; Martin, Nicholas G; Montgomery, Grant W; North, Kari E; Pedersen, Nancy L; Spector, Timothy D; Speliotes, Elizabeth K; Goddard, Michael E; Yang, Jian; Visscher, Peter M

2015-11-01

Across-nation differences in the mean values for complex traits are common, but the reasons for these differences are unknown. Here we find that many independent loci contribute to population genetic differences in height and body mass index (BMI) in 9,416 individuals across 14 European countries. Using discovery data on over 250,000 individuals and unbiased effect size estimates from 17,500 sibling pairs, we estimate that 24% (95% credible interval (CI) = 9%, 41%) and 8% (95% CI = 4%, 16%) of the captured additive genetic variance for height and BMI, respectively, reflect population genetic differences. Population genetic divergence differed significantly from that in a null model (height, P < 3.94 × 10(-8); BMI, P < 5.95 × 10(-4)), and we find an among-population genetic correlation for tall and slender individuals (r = -0.80, 95% CI = -0.95, -0.60), consistent with correlated selection for both phenotypes. Observed differences in height among populations reflected the predicted genetic means (r = 0.51; P < 0.001), but environmental differences across Europe masked genetic differentiation for BMI (P < 0.58).

Excitation-based and informational masking of a tonal signal in a four-tone masker.

PubMed

Leibold, Lori J; Hitchens, Jack J; Buss, Emily; Neff, Donna L

2010-04-01

This study examined contributions of peripheral excitation and informational masking to the variability in masking effectiveness observed across samples of multi-tonal maskers. Detection thresholds were measured for a 1000-Hz signal presented simultaneously with each of 25, four-tone masker samples. Using a two-interval, forced-choice adaptive task, thresholds were measured with each sample fixed throughout trial blocks for ten listeners. Average thresholds differed by as much as 26 dB across samples. An excitation-based model of partial loudness [Moore, B. C. J. et al. (1997). J. Audio Eng. Soc. 45, 224-237] was used to predict thresholds. These predictions accounted for a significant portion of variance in the data of several listeners, but no relation between the model and data was observed for many listeners. Moreover, substantial individual differences, on the order of 41 dB, were observed for some maskers. The largest individual differences were found for maskers predicted to produce minimal excitation-based masking. In subsequent conditions, one of five maskers was randomly presented in each interval. The difference in performance for samples with low versus high predicted thresholds was reduced in random compared to fixed conditions. These findings are consistent with a trading relation whereby informational masking is largest for conditions in which excitation-based masking is smallest.

Noise exposure-response relationships established from repeated binary observations: Modeling approaches and applications.

PubMed

Schäffer, Beat; Pieren, Reto; Mendolia, Franco; Basner, Mathias; Brink, Mark

2017-05-01

Noise exposure-response relationships are used to estimate the effects of noise on individuals or a population. Such relationships may be derived from independent or repeated binary observations, and modeled by different statistical methods. Depending on the method by which they were established, their application in population risk assessment or estimation of individual responses may yield different results, i.e., predict "weaker" or "stronger" effects. As far as the present body of literature on noise effect studies is concerned, however, the underlying statistical methodology to establish exposure-response relationships has not always been paid sufficient attention. This paper gives an overview on two statistical approaches (subject-specific and population-averaged logistic regression analysis) to establish noise exposure-response relationships from repeated binary observations, and their appropriate applications. The considerations are illustrated with data from three noise effect studies, estimating also the magnitude of differences in results when applying exposure-response relationships derived from the two statistical approaches. Depending on the underlying data set and the probability range of the binary variable it covers, the two approaches yield similar to very different results. The adequate choice of a specific statistical approach and its application in subsequent studies, both depending on the research question, are therefore crucial.

Activity Level in the Lab: Overlap with Shyness Indicates It is More than Pure Motoric Activity

ERIC Educational Resources Information Center

Frazier-Wood, Alexis C.; Saudino, Kimberly J.

2017-01-01

The observation that children's activity level (AL) differs between novel and familiar situations is well established. What influences individual differences in how AL is different across these situations is less well understood. Drawing on animal literature, which links rats' AL when 1st placed in a novel setting with novelty seeking phenotypes,…

Quantitative analysis of formal caregivers' use of communication strategies while assisting individuals with moderate and severe Alzheimer's disease during oral care.

PubMed

Wilson, Rozanne; Rochon, Elizabeth; Mihailidis, Alex; Leonard, Carol

2013-01-01

This cross-sectional observational study examined formal caregivers' use of task-focused and social communication strategies while assisting individuals with moderate and severe Alzheimer's disease residing in a long-term care facility during a basic activity of daily living: toothbrushing. Thirteen formal caregiver-resident dyads were observed during a total of 78 separate toothbrushing sessions. All caregiver utterances occurring during the task were transcribed and coded for type of communication strategy utilizing a multidimensional observational coding scheme, which was developed a priori. Overall, the majority of residents, irrespective of disease severity, successfully completed toothbrushing with the support of caregiver assistance. Caregivers assisting residents with moderate and severe AD were found to use a variety of communication strategies, with task-focused strategies accounting for the majority of use. For the most part, the communicative strategies employed did not differ across disease severity. However, some differences were identified including the use of one proposition, paraphrased repetition, using the resident's name, and provision of full assistance, with these strategies being used more often when assisting individuals with severe AD. This study adds to the emerging literature supporting the use of specific communication strategies while assisting residents with AD during the completion of daily tasks. From reviewing this study, readers will be able to identify a variety of communication strategies, both task-focused and relational, that formal caregivers utilize while assisting residents with moderate and severe Alzheimer's disease (AD) during a basic activity of daily living. Furthermore, the reader will be able to distinguish between communication strategies that are optimal when assisting individuals with moderate AD as compared to assisting individuals with severe AD. Copyright © 2013 Elsevier Inc. All rights reserved.

Postoperative changes in in vivo measured friction in total hip joint prosthesis during walking.

PubMed

Damm, Philipp; Bender, Alwina; Bergmann, Georg

2015-01-01

Loosening of the artificial cup and inlay is the most common reasons for total hip replacement failures. Polyethylene wear and aseptic loosening are frequent reasons. Furthermore, over the past few decades, the population of patients receiving total hip replacements has become younger and more active. Hence, a higher level of activity may include an increased risk of implant loosening as a result of friction-induced wear. In this study, an instrumented hip implant was used to measure the contact forces and friction moments in vivo during walking. Subsequently, the three-dimensional coefficient of friction in vivo was calculated over the whole gait cycle. Measurements were collected from ten subjects at several time points between three and twelve months postoperative. No significant change in the average resultant contact force was observed between three and twelve months postoperative. In contrast, a significant decrease of up to 47% was observed in the friction moment. The coefficient of friction also decreased over postoperative time on average. These changes may be caused by 'running-in' effects of the gliding components or by the improved lubricating properties of the synovia. Because the walking velocity and contact forces were found to be nearly constant during the observed period, the decrease in friction moment suggests an increase in fluid viscosity. The peak values of the contact force individually varied by 32%-44%. The friction moment individually differed much more, by 110%-129% at three and up to 451% at twelve months postoperative. The maximum coefficient of friction showed the highest individual variability, about 100% at three and up to 914% at twelve months after surgery. These individual variations in the friction parameters were most likely due to different 'running-in' effects that were influenced by the individual activity levels and synovia properties.

Population structure and residency patterns of whale sharks, Rhincodon typus, at a provisioning site in Cebu, Philippines

PubMed Central

Lucey, Anna; Labaja, Jessica; So, Catherine Lee; Snow, Sally; Ponzo, Alessandro

2014-01-01

This study represents the first description of whale sharks, Rhincodon typus, occurring at a provisioning site in Oslob, Cebu, Philippines. Frequent observations of sharks are often difficult, even at tourism sites, giving rise to provisioning activities to attract them. The present study provides repeated longitudinal data at a site where daily provisioning activities took place, and whale sharks were present every day. A total of 158 individual whale sharks were photographically identified between Mar 2012 and Dec 2013, with 129 males (82%), 19 females (12%) and 10 (6%) of undetermined sex. Mean estimated total length was 5.5 m (±1.3 m S.D.). Twenty individuals were measured with laser photogrammetry to validate researchers’ estimated sizes, yielding a good correlation (r2 = 0.83). Fifty-four (34%) individuals were observed being hand-fed by local fishermen (provisioned), through in-water behavioural observations. Maximum likelihood methods were used to model mean residency time of 44.9 days (±20.6 days S.E.) for provisioned R. typus contrasting with 22.4 days (±8.9 days S.E.) for non-provisioned individuals. Propeller scars were observed in 47% of the animals. A mean of 12.7 (±4.3 S.D.) R. typus were present in the survey area daily, with a maximum of 26 individuals (Aug 10 2013) and a minimum of 2 (Dec 6 2012). Twelve (8%) individuals were seen on at least 50% of survey days (n = 621), with a maximum residency of 572 days for one individual (P-396). Twenty four individuals were photographically identified across regional hotsposts, highlighting the species’ migratory nature and distribution. Extended residency and differences in lagged identification rates suggest behavioural modification on provisioned individuals, underlying the necessity for proper management of this tourism activity. PMID:25279256

Swim Speed, Behavior, and Movement of North Atlantic Right Whales (Eubalaena glacialis) in Coastal Waters of Northeastern Florida, USA

PubMed Central

Hain, James H. W.; Hampp, Joy D.; McKenney, Sheila A.; Albert, Julie A.; Kenney, Robert D.

2013-01-01

In a portion of the coastal waters of northeastern Florida, North Atlantic right whales (Eubalaena glacialis) occur close to shore from December through March. These waters are included within the designated critical habitat for right whales. Data on swim speed, behavior, and direction of movement – with photo-identification of individual whales – were gathered by a volunteer sighting network working alongside experienced scientists and supplemented by aerial observations. In seven years (2001–2007), 109 tracking periods or “follows” were conducted on right whales during 600 hours of observation from shore-based observers. The whales were categorized as mother-calf pairs, singles and non-mother-calf pairs, and groups of 3 or more individuals. Sample size and amount of information obtained was largest for mother-calf pairs. Swim speeds varied within and across observation periods, individuals, and categories. One category, singles and non mother-calf pairs, was significantly different from the other two – and had the largest variability and the fastest swim speeds. Median swim speed for all categories was 1.3 km/h (0.7 kn), with examples that suggest swim speeds differ between within-habitat movement and migration-mode travel. Within-habitat right whales often travel back-and-forth in a north-south, along-coast, direction, which may cause an individual to pass by a given point on several occasions, potentially increasing anthropogenic risk exposure (e.g., vessel collision, fishing gear entanglement, harassment). At times, mothers and calves engaged in lengthy stationary periods (up to 7.5 h) that included rest, nursing, and play. These mother-calf interactions have implications for communication, learning, and survival. Overall, these behaviors are relevant to population status, distribution, calving success, correlation to environmental parameters, survey efficacy, and human-impacts mitigation. These observations contribute important parameters to conservation biology, predictive modeling, and management. However, while we often search for predictions, patterns, and means, the message here is also about variability and the behavioral characteristics of individual whales. PMID:23326603

Emergence of Leadership within a Homogeneous Group

PubMed Central

Eskridge, Brent E.; Valle, Elizabeth; Schlupp, Ingo

2015-01-01

Large scale coordination without dominant, consistent leadership is frequent in nature. How individuals emerge from within the group as leaders, however transitory this position may be, has become an increasingly common question asked. This question is further complicated by the fact that in many of these aggregations, differences between individuals are minor and the group is largely considered to be homogeneous. In the simulations presented here, we investigate the emergence of leadership in the extreme situation in which all individuals are initially identical. Using a mathematical model developed using observations of natural systems, we show that the addition of a simple concept of leadership tendencies which is inspired by observations of natural systems and is affected by experience can produce distinct leaders and followers using a nonlinear feedback loop. Most importantly, our results show that small differences in experience can promote the rapid emergence of stable roles for leaders and followers. Our findings have implications for our understanding of adaptive behaviors in initially homogeneous groups, the role experience can play in shaping leadership tendencies, and the use of self-assessment in adapting behavior and, ultimately, self-role-assignment. PMID:26226381

Emergence of Leadership within a Homogeneous Group.

PubMed

Eskridge, Brent E; Valle, Elizabeth; Schlupp, Ingo

2015-01-01

Large scale coordination without dominant, consistent leadership is frequent in nature. How individuals emerge from within the group as leaders, however transitory this position may be, has become an increasingly common question asked. This question is further complicated by the fact that in many of these aggregations, differences between individuals are minor and the group is largely considered to be homogeneous. In the simulations presented here, we investigate the emergence of leadership in the extreme situation in which all individuals are initially identical. Using a mathematical model developed using observations of natural systems, we show that the addition of a simple concept of leadership tendencies which is inspired by observations of natural systems and is affected by experience can produce distinct leaders and followers using a nonlinear feedback loop. Most importantly, our results show that small differences in experience can promote the rapid emergence of stable roles for leaders and followers. Our findings have implications for our understanding of adaptive behaviors in initially homogeneous groups, the role experience can play in shaping leadership tendencies, and the use of self-assessment in adapting behavior and, ultimately, self-role-assignment.

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

Ma, Ying, E-mail: yingma@imr.ac.cn; Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Science; An, Boxing

By using an electron donor–acceptor molecule that consists of a perylenediimide (PDI) core bonded with two ferrocene (Fc) units, well-defined nanorods, nanowires and microwires of PDI-Fc were formed through simply adjusting the initial concentration of PDI-Fc in dichloromethane or CH{sub 2}Cl{sub 2}. Moreover, the two-ended devices based on individual microwire were fabricated. Highly reproducible and sensitive photo response characteristics were demonstrated in the microwire through controlling the white light on and off with different light intensities. The assembly strategy via complementary donors and acceptors is of significance for constructing photoconductive systems and developing novel functional devices. - Graphical abstract: Themore » two-ended devices based on individual microwire were fabricated. Highly reproducible and sensitive photo response characteristics were observed by controlling the white light on and off with different light intensities. - Highlights: • An electron donor–acceptor molecule (PDI-Fc) was synthesized. • Well-defined nanorods, nanowires and microwires of PDI-Fc were formed. • The two-ended devices based on individual microwire were fabricated. • Highly reproducible and sensitive photo response characteristics were observed.« less

A multilevel study on the association of observer-assessed working conditions with depressive symptoms among female eldercare workers from 56 work units in 10 care homes in Denmark.

PubMed

Jakobsen, Louise M; Jorgensen, Anette F B; Thomsen, Birthe L; Greiner, Birgit A; Rugulies, Reiner

2015-11-11

Eldercare workers in Denmark have a higher prevalence of poor psychological health than other occupational groups. We examined the association between working conditions assessed by trained observers and depressive symptoms assessed by self-report in a study of female Danish eldercare workers. Working conditions were observed based on action regulation theory and defined as (1) regulation requirements, a workplace resource providing opportunity for decision-making and skill development and (2) barriers for task completion. We examined the associations of individual and work unit averaged working conditions with depressive symptoms in a sample of 95 individually observed eldercare workers. Further, we examined the association of work unit averaged working conditions with depressive symptoms in a sample of 205 care workers, including both observed and non-observed individuals. We used regression models that allowed for correlations within work units and care homes and adjusted these models for demographics, job characteristics and stressful life events. Higher levels of regulation requirements were associated with lower depressive symptoms at the individual level (p=0.04), but not at the workplace level. Barriers were not associated with depressive symptoms at the individual level. At the workplace level, a higher number of qualitatively different barriers (p=0.04) and a higher number of barriers for equipment use (p=0.03) were associated with lower levels of depressive symptoms in the age and cohabitation adjusted model, however statistical significance was lost in the fully adjusted model. Low level of regulation requirements was associated with a high level of depressive symptoms. The study highlights the importance of examining both individual and workplace levels of working conditions. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

Enteroendocrine K and L cells in healthy and type 2 diabetic individuals.

PubMed

Jorsal, Tina; Rhee, Nicolai A; Pedersen, Jens; Wahlgren, Camilla D; Mortensen, Brynjulf; Jepsen, Sara L; Jelsing, Jacob; Dalbøge, Louise S; Vilmann, Peter; Hassan, Hazem; Hendel, Jakob W; Poulsen, Steen S; Holst, Jens J; Vilsbøll, Tina; Knop, Filip K

2018-02-01

Enteroendocrine K and L cells are pivotal in regulating appetite and glucose homeostasis. Knowledge of their distribution in humans is sparse and it is unknown whether alterations occur in type 2 diabetes. We aimed to evaluate the distribution of enteroendocrine K and L cells and relevant prohormone-processing enzymes (using immunohistochemical staining), and to evaluate the mRNA expression of the corresponding genes along the entire intestinal tract in individuals with type 2 diabetes and healthy participants. In this cross-sectional study, 12 individuals with type 2 diabetes and 12 age- and BMI-matched healthy individuals underwent upper and lower double-balloon enteroscopy with mucosal biopsy retrieval from approximately every 30 cm of the small intestine and from seven specific anatomical locations in the large intestine. Significantly different densities for cells positive for chromogranin A (CgA), glucagon-like peptide-1, glucose-dependent insulinotropic polypeptide, peptide YY, prohormone convertase (PC) 1/3 and PC2 were observed along the intestinal tract. The expression of CHGA did not vary along the intestinal tract, but the mRNA expression of GCG, GIP, PYY, PCSK1 and PCSK2 differed along the intestinal tract. Lower counts of CgA-positive and PC1/3-positive cells, respectively, were observed in the small intestine of individuals with type 2 diabetes compared with healthy participants. In individuals with type 2 diabetes compared with healthy participants, the expression of GCG and PYY was greater in the colon, while the expression of GIP and PCSK1 was greater in the small intestine and colon, and the expression of PCSK2 was greater in the small intestine. Our findings provide a detailed description of the distribution of enteroendocrine K and L cells and the expression of their products in the human intestinal tract and demonstrate significant differences between individuals with type 2 diabetes and healthy participants. NCT03044860.

Morphological and behavioral differences in the gastropod Trophon geversianus associated to distinct environmental conditions, as revealed by a multidisciplinary approach

NASA Astrophysics Data System (ADS)

Márquez, Federico; Nieto Vilela, Rocío Aimé; Lozada, Mariana; Bigatti, Gregorio

2015-01-01

The gastropod Trophon geversianus exhibits shell polymorphisms along its distribution in subtidal and intertidal habitats. Our hypothesis is that morphological and behavioral patterns of T. geversianus represent habitat-specific constrains; subsequently we expect an association between shell morphology, attachment behavior, and habitat. In order to test this hypothesis we compared individuals from intertidal and subtidal habitats, at three sites in Golfo Nuevo (Argentina). We analyzed shell morphology using classic morphometric variables, 3D geometric morphometrics and computing tomography scan. The results were complemented with field observations of attachment to substrate and turning time behavior, as well as of the number of shell scars produced by crab predation. Our results showed differences in shell size and shape between intertidal and subtidal-collected individuals. Centroid size, total weight and shell weight, as well as shell density and thickness were significantly lower in intertidal individuals than in subtidal ones. Gastropods from intertidal habitats presented a low-spired shell and an expanded aperture which might allow better attachment to the bottom substrate, while subtidal individuals presented a slender and narrower shell shape. The number of crab scars was significantly higher in shells from subtidal individuals. Observations of the behavior of gastropods placed at the intertidal splash zone showed 100% of attachment to the bottom in the intertidal individuals, while subtidal specimens only attached in average in 32% of the cases. These latter took 12 times longer to re-attach to the bottom when faced up. Phylogenetic analysis of COI gene fragments showed no consistent differences among individuals sampled in both habitats. All these results suggest that T. geversianus has developed two ecomorphs with distinct morphological and behavioral responses to physically stressful conditions registered in north Patagonian intertidals, as opposed to lower physical stress but higher predation pressure in the subtidal habitats. The findings of this work constitute a starting point in the study of ecological adaptation processes in gastropods from Patagonian coastal environments.

Individual Differences in Dynamic Functional Brain Connectivity across the Human Lifespan.

PubMed

Davison, Elizabeth N; Turner, Benjamin O; Schlesinger, Kimberly J; Miller, Michael B; Grafton, Scott T; Bassett, Danielle S; Carlson, Jean M

2016-11-01

Individual differences in brain functional networks may be related to complex personal identifiers, including health, age, and ability. Dynamic network theory has been used to identify properties of dynamic brain function from fMRI data, but the majority of analyses and findings remain at the level of the group. Here, we apply hypergraph analysis, a method from dynamic network theory, to quantify individual differences in brain functional dynamics. Using a summary metric derived from the hypergraph formalism-hypergraph cardinality-we investigate individual variations in two separate, complementary data sets. The first data set ("multi-task") consists of 77 individuals engaging in four consecutive cognitive tasks. We observe that hypergraph cardinality exhibits variation across individuals while remaining consistent within individuals between tasks; moreover, the analysis of one of the memory tasks revealed a marginally significant correspondence between hypergraph cardinality and age. This finding motivated a similar analysis of the second data set ("age-memory"), in which 95 individuals, aged 18-75, performed a memory task with a similar structure to the multi-task memory task. With the increased age range in the age-memory data set, the correlation between hypergraph cardinality and age correspondence becomes significant. We discuss these results in the context of the well-known finding linking age with network structure, and suggest that hypergraph analysis should serve as a useful tool in furthering our understanding of the dynamic network structure of the brain.

Distraction Control Processes in Free Recall: Benefits and Costs to Performance

ERIC Educational Resources Information Center

Marsh, John E.; Sörqvist, Patrik; Hodgetts, Helen M.; Beaman, C. Philip; Jones, Dylan M.

2015-01-01

How is semantic memory influenced by individual differences under conditions of distraction? This question was addressed by observing how participants recalled visual target words-drawn from a single category-while ignoring spoken distractor words that were members of either the same or a different (single) category. Working memory capacity (WMC)…

Spatial task performance, sex differences, and motion sickness susceptibility.

PubMed

Levine, Max E; Stern, Robert M

2002-10-01

There are substantial individual differences in susceptibility to motion sickness, yet little is known about what mediates these differences. Spatial ability and sex have been suggested as possible factors in this relationship. 89 participants (57 women) were administered a Motion Sickness Questionnaire that assesses motion sickness susceptibility, a Water-level Task that gauges sensitivity to gravitational upright, and a Mental Rotation Task that tests an individual's awareness of how objects typically move in space. Significant sex differences were observed in performance of both the Water-level Task (p<.01), and the Mental Rotation Task (p<.005), with women performing less accurately than men. Women also had significantly higher scores on the Motion Sickness Questionnaire (p<.005). Among men, but not women, significant negative relationships were observed between Water-level Task performance and Motion Sickness Questionnaire score (p<.001) and between Mental Rotation Task performance and Motion Sickness Questionnaire score (p<.005). In conclusion, women performed significantly more poorly than men did on the spatial ability tasks and reported significantly more bouts of motion sickness. In addition, men showed a significant negative relationship between spatial ability and motion sickness susceptibility.

Juvenile movement among different populations of Cutthroat Trout introduced as embryos to vacant habitat

USGS Publications Warehouse

Andrews, Tessa M.; Shepard, Bradley B.; Litt, Andrea R.; Kruse, Carter G.; Zale, Alexander V.; Kalinowski, Steven T.

2013-01-01

Translocations are frequently used to increase the abundance and range of endangered fishes. One factor likely to affect the outcome of translocations is fish movement. We introduced embryos from five Westslope Cutthroat Trout Oncorhynchus clarkii lewisipopulations (both hatchery and wild) at five different locations within a fishless watershed. We then examined the movement of age-1 and age-2 fish and looked for differences in movement distance among source populations and among introduction sites; we also examined the interactions among age, population, and introduction site. At age 1, most individuals (90.9%) remained within 1,000 m their introduction sites. By age 2, the majority of individuals (58.3%) still remained within 1,000 m of their introduction site, but considerably more individuals had moved downstream, some more than 6,000 m from their introduction site. We observed a significant interaction between age and source population (F 4, 1077 = 15.45, P < 0.0001) as well as between age and introduction site (F 41, 1077 = 11.39, P < 0.0008), so we presented results in the context of these interactions. Within age-groups, we observed differences in movement behavior among source populations and among donor populations of Westslope Cutthroat Trout. We discuss these findings in light of previous research on juvenile salmonid movement.

Extending the Functionality of Behavioural Change-Point Analysis with k-Means Clustering: A Case Study with the Little Penguin (Eudyptula minor)

PubMed Central

Zhang, Jingjing; Dennis, Todd E.

2015-01-01

We present a simple framework for classifying mutually exclusive behavioural states within the geospatial lifelines of animals. This method involves use of three sequentially applied statistical procedures: (1) behavioural change point analysis to partition movement trajectories into discrete bouts of same-state behaviours, based on abrupt changes in the spatio-temporal autocorrelation structure of movement parameters; (2) hierarchical multivariate cluster analysis to determine the number of different behavioural states; and (3) k-means clustering to classify inferred bouts of same-state location observations into behavioural modes. We demonstrate application of the method by analysing synthetic trajectories of known ‘artificial behaviours’ comprised of different correlated random walks, as well as real foraging trajectories of little penguins (Eudyptula minor) obtained by global-positioning-system telemetry. Our results show that the modelling procedure correctly classified 92.5% of all individual location observations in the synthetic trajectories, demonstrating reasonable ability to successfully discriminate behavioural modes. Most individual little penguins were found to exhibit three unique behavioural states (resting, commuting/active searching, area-restricted foraging), with variation in the timing and locations of observations apparently related to ambient light, bathymetry, and proximity to coastlines and river mouths. Addition of k-means clustering extends the utility of behavioural change point analysis, by providing a simple means through which the behaviours inferred for the location observations comprising individual movement trajectories can be objectively classified. PMID:25922935

Extending the Functionality of Behavioural Change-Point Analysis with k-Means Clustering: A Case Study with the Little Penguin (Eudyptula minor).

PubMed

Zhang, Jingjing; O'Reilly, Kathleen M; Perry, George L W; Taylor, Graeme A; Dennis, Todd E

2015-01-01

We present a simple framework for classifying mutually exclusive behavioural states within the geospatial lifelines of animals. This method involves use of three sequentially applied statistical procedures: (1) behavioural change point analysis to partition movement trajectories into discrete bouts of same-state behaviours, based on abrupt changes in the spatio-temporal autocorrelation structure of movement parameters; (2) hierarchical multivariate cluster analysis to determine the number of different behavioural states; and (3) k-means clustering to classify inferred bouts of same-state location observations into behavioural modes. We demonstrate application of the method by analysing synthetic trajectories of known 'artificial behaviours' comprised of different correlated random walks, as well as real foraging trajectories of little penguins (Eudyptula minor) obtained by global-positioning-system telemetry. Our results show that the modelling procedure correctly classified 92.5% of all individual location observations in the synthetic trajectories, demonstrating reasonable ability to successfully discriminate behavioural modes. Most individual little penguins were found to exhibit three unique behavioural states (resting, commuting/active searching, area-restricted foraging), with variation in the timing and locations of observations apparently related to ambient light, bathymetry, and proximity to coastlines and river mouths. Addition of k-means clustering extends the utility of behavioural change point analysis, by providing a simple means through which the behaviours inferred for the location observations comprising individual movement trajectories can be objectively classified.

Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types

PubMed Central

PITHON, Matheus Melo; da MATA, Kayure Rocha; ROCHA, Karina Silva; COSTA, Brenda do Nascimento; NEVES, Fernando; BARBOSA, George Caique Gouveia; COQUEIRO, Raildo da Silva

2014-01-01

Objective Evaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals. Material and Methods The image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%). To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA). The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%. Results Brachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators. Conclusion To achieve an enhanced esthetic smile it is necessary to observe the patient's facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive. PMID:25466472

Perceptions of brachyfacial, mesofacial and dolichofacial individuals with regard to the buccal corridor in different facial types.

PubMed

Pithon, Matheus Melo; Mata, Kayure Rocha da; Rocha, Karina Silva; Costa, Brenda do Nascimento; Neves, Fernando; Barbosa, George Caique Gouveia; Coqueiro, Raildo da Silva

2014-01-01

Evaluate the esthetic perception and attractiveness of the smile with regard to the buccal corridor in different facial types by brachyfacial, mesofacial and dolichofacial individuals. The image of a smiling individual with a mesofacial type of face was changed to create three different facial types with five different buccal corridors (2%, 10%, 15%, 22% and 28%). To achieve this effect, a photo editing software was used (Adobe Photoshop, Adobe Systems Inc, San Francisco, CA, EUA). The images were submitted to evaluators with brachyfacial, mesofacial and dolichofacial types of faces, who evaluated the degree of esthetic perception and attractiveness by means of a visual analog scale measuring 70 mm. The differences between evaluators were verified by the Mann-Whitney test. All statistics were performed with a confidence level of 95%. Brachyfacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2% as more attractive. Mesofacial individuals perceived mesofacial and dolichofacial types of faces with buccal corridor of 2%, 10% and 15% as more attractive. Dolichofacial individuals perceived the mesofacial type of face with buccal corridor of 2% as more attractive. Evaluators of the female sex generally attributed higher scores than the male evaluators. To achieve an enhanced esthetic smile it is necessary to observe the patient's facial type. The preference for narrow buccal corridors is an esthetic characteristic preferred by men and women, and wide buccal corridors are less attractive.

Chromosome heteromorphism quantified by high-resolution bivariate flow karyotyping.

PubMed Central

Trask, B; van den Engh, G; Mayall, B; Gray, J W

1989-01-01

Maternal and paternal homologues of many chromosome types can be differentiated on the basis of their peak position in Hoechst 33258 versus chromomycin A3 bivariate flow karyotypes. We demonstrate here the magnitude of DNA content differences among normal chromosomes of the same type. Significant peak-position differences between homologues were observed for an average of four chromosome types in each of the karyotypes of 98 different individuals. The frequency of individuals with differences in homologue peak positions varied among chromosome types: e.g., chromosome 15, 61%; chromosome 3, 4%. Flow karyotypes of 33 unrelated individuals were compared to determine the range of peak position among normal chromosomes. Chromosomes Y, 21, 22, 15, 16, 13, 14, and 19 were most heteromorphic, and chromosomes 2-8 and X were least heteromorphic. The largest chromosome 21 was 45% larger than the smallest 21 chromosome observed. The base composition of the variable regions differed among chromosome types. DNA contents of chromosome variants determined from flow karyotypes were closely correlated to measurements of DNA content made of gallocyanin chrome alum-stained metaphase chromosomes on slides. Fluorescence in situ hybridization with chromosome-specific repetitive sequences indicated that variability in their copy number is partly responsible for peak-position variability in some chromosomes. Heteromorphic chromosomes are identified for which parental flow karyotype information will be essential if de novo rearrangements resulting in small DNA content changes are to be detected with flow karyotyping. Images Figure 5 PMID:2479266

Number sense across the lifespan as revealed by a massive Internet-based sample

PubMed Central

Halberda, Justin; Ly, Ryan; Wilmer, Jeremy B.; Naiman, Daniel Q.; Germine, Laura

2012-01-01

It has been difficult to determine how cognitive systems change over the grand time scale of an entire life, as few cognitive systems are well enough understood; observable in infants, adolescents, and adults; and simple enough to measure to empower comparisons across vastly different ages. Here we address this challenge with data from more than 10,000 participants ranging from 11 to 85 years of age and investigate the precision of basic numerical intuitions and their relation to students’ performance in school mathematics across the lifespan. We all share a foundational number sense that has been observed in adults, infants, and nonhuman animals, and that, in humans, is generated by neurons in the intraparietal sulcus. Individual differences in the precision of this evolutionarily ancient number sense may impact school mathematics performance in children; however, we know little of its role beyond childhood. Here we find that population trends suggest that the precision of one’s number sense improves throughout the school-age years, peaking quite late at ∼30 y. Despite this gradual developmental improvement, we find very large individual differences in number sense precision among people of the same age, and these differences relate to school mathematical performance throughout adolescence and the adult years. The large individual differences and prolonged development of number sense, paired with its consistent and specific link to mathematics ability across the age span, hold promise for the impact of educational interventions that target the number sense. PMID:22733748

Many private mutations originate from the first few divisions of a human colorectal adenoma.

PubMed

Kang, Haeyoun; Salomon, Matthew P; Sottoriva, Andrea; Zhao, Junsong; Toy, Morgan; Press, Michael F; Curtis, Christina; Marjoram, Paul; Siegmund, Kimberly; Shibata, Darryl

2015-11-01

Intratumoural mutational heterogeneity (ITH) or the presence of different private mutations in different parts of the same tumour is commonly observed in human tumours. The mechanisms generating such ITH are uncertain. Here we find that ITH can be remarkably well structured by measuring point mutations, chromosome copy numbers, and DNA passenger methylation from opposite sides and individual glands of a 6 cm human colorectal adenoma. ITH was present between tumour sides and individual glands, but the private mutations were side-specific and subdivided the adenoma into two major subclones. Furthermore, ITH disappeared within individual glands because the glands were clonal populations composed of cells with identical mutant genotypes. Despite mutation clonality, the glands were relatively old, diverse populations when their individual cells were compared for passenger methylation and by FISH. These observations can be organized into an expanding star-like ancestral tree with co-clonal expansion, where many private mutations and multiple related clones arise during the first few divisions. As a consequence, most detectable mutational ITH in the final tumour originates from the first few divisions. Much of the early history of a tumour, especially the first few divisions, may be embedded within the detectable ITH of tumour genomes. Copyright © 2015 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

Immediate effects of adding mental practice to physical practice on the gait of individuals with Parkinson's disease: Randomized clinical trial.

PubMed

Santiago, Lorenna Marques de Melo; de Oliveira, Daniel Antunes; de Macêdo Ferreira, Louise Gabriella Lopes; de Brito Pinto, Hyanne Yasmim; Spaniol, Ana Paula; de Lucena Trigueiro, Larissa Coutinho; Ribeiro, Tatiana Souza; de Sousa, Angélica Vieira Cavalcanti; Piemonte, Maria Elisa Pimentel; Lindquist, Ana Raquel Rodrigues

2015-01-01

Mental practice has shown benefits in the rehabilitation of neurological patients, however, there is no evidence of immediate effects on gait of individuals with Parkinson's disease. Determine the effects of mental practice activity added to physical practice on the gait of individuals with Idiopathic Parkinson's Disease (IPD). 20 patients classified with stage 2 and 3, according to the Hoehn and Yahr scale were randomized into 2 groups. The experimental group (N = 10) was submitted to a single session of mental practice and physical practice gait protocol and the control group (N = 10) only to physical practice. The primary outcomes were stride length and total stance and swing time. Secondary outcomes were hip range of motion, velocity and mobility. Subjects were reassessed 10 minutes, 1 day and 7 days after the end of the session. There was no statistically significant difference between the groups. An intragroup difference was observed in velocity, stride length, hip range of motion, and mobility, as well as total stance and swing time. These results were also observed on follow-ups. Mental practice did not have a greater effect on the gait of individuals with IPD than physical practice, after a single session.

The structure of people's hair.

PubMed

Yang, Fei-Chi; Zhang, Yuchen; Rheinstädter, Maikel C

2014-01-01

Hair is a filamentous biomaterial consisting mainly of proteins in particular keratin. The structure of human hair is well known: the medulla is a loosely packed, disordered region near the centre of the hair surrounded by the cortex, which contains the major part of the fibre mass, mainly consisting of keratin proteins and structural lipids. The cortex is surrounded by the cuticle, a layer of dead, overlapping cells forming a protective layer around the hair. The corresponding structures have been studied extensively using a variety of different techniques, such as light, electron and atomic force microscopes, and also X-ray diffraction. We were interested in the question how much the molecular hair structure differs from person to person, between male and female hair, hair of different appearances such as colour and waviness. We included hair from parent and child, identical and fraternal twins in the study to see if genetically similar hair would show similar structural features. The molecular structure of the hair samples was studied using high-resolution X-ray diffraction, which covers length scales from molecules up to the organization of secondary structures. Signals due to the coiled-coil phase of α-helical keratin proteins, intermediate keratin filaments in the cortex and from the lipid layers in the cell membrane complex were observed in the specimen of all individuals, with very small deviations. Despite the relatively small number of individuals (12) included in this study, some conclusions can be drawn. While the general features were observed in all individuals and the corresponding molecular structures were almost identical, additional signals were observed in some specimen and assigned to different types of lipids in the cell membrane complex. Genetics seem to play a role in this composition as identical patterns were observed in hair from father and daughter and identical twins, however, not for fraternal twins. Identification and characterization of these features is an important step towards the detection of abnormalities in the molecular structure of hair as a potential diagnostic tool for certain diseases.

Cross-sex hormonal treatment and body uneasiness in individuals with gender dysphoria.

PubMed

Fisher, Alessandra D; Castellini, Giovanni; Bandini, Elisa; Casale, Helen; Fanni, Egidia; Benni, Laura; Ferruccio, Naika; Meriggiola, Maria Cristina; Manieri, Chiara; Gualerzi, Anna; Jannini, Emmanuele; Oppo, Alessandro; Ricca, Valdo; Maggi, Mario; Rellini, Alessandra H

2014-03-01

Cross-sex hormonal treatment (CHT) used for gender dysphoria (GD) could by itself affect well-being without the use of genital surgery; however, to date, there is a paucity of studies investigating the effects of CHT alone. This study aimed to assess differences in body uneasiness and psychiatric symptoms between GD clients taking CHT and those not taking hormones (no CHT). A second aim was to assess whether length of CHT treatment and daily dose provided an explanation for levels of body uneasiness and psychiatric symptoms. A consecutive series of 125 subjects meeting the criteria for GD who not had genital reassignment surgery were considered. Subjects were asked to complete the Body Uneasiness Test (BUT) to explore different areas of body-related psychopathology and the Symptom Checklist-90 Revised (SCL-90-R) to measure psychological state. In addition, data on daily hormone dose and length of hormonal treatment (androgens, estrogens, and/or antiandrogens) were collected through an analysis of medical records. Among the male-to-female (MtF) individuals, those using CHT reported less body uneasiness compared with individuals in the no-CHT group. No significant differences were observed between CHT and no-CHT groups in the female-to-male (FtM) sample. Also, no significant differences in SCL score were observed with regard to gender (MtF vs. FtM), hormone treatment (CHT vs. no-CHT), or the interaction of these two variables. Moreover, a two-step hierarchical regression showed that cumulative dose of estradiol (daily dose of estradiol times days of treatment) and cumulative dose of androgen blockers (daily dose of androgen blockers times days of treatment) predicted BUT score even after controlling for age, gender role, cosmetic surgery, and BMI. The differences observed between MtF and FtM individuals suggest that body-related uneasiness associated with GD may be effectively diminished with the administration of CHT even without the use of genital surgery for MtF clients. A discussion is provided on the importance of controlling both length and daily dose of treatment for the most effective impact on body uneasiness. © 2013 International Society for Sexual Medicine.

[The tuberculin skin test in BCG-vaccinated individualse].

PubMed

Miret Cuadras, P; Pina Gutiérrez, J M

1998-10-01

The aim of this study was to evaluate the tuberculin skin test in individuals vaccinated with bacillus Calmette-Guérin (BCG) using 2 IU of RT-23. One hundred ninety-six individuals aged 22-40 years-old who had been vaccinated with BCG between 1965 and 1974 were enrolled along with 375 non-vaccinated individuals of the same age and with similar level of risk of infection. The positive predictive value of the test was assessed for three levels of response as indicated by areas of thickening in three diameters: 5, 10 and 15 mm. Vaccinated individuals with negative results were given a second skin test 7 days later to detect a booster effect. Positive diameters 5 mm were observed in 66% of the vaccinated individuals and 24% of the non-vaccinated subjects. Positive diameters 10 mm were observed in 51% of the vaccinated individuals and 19% of the non vaccinated ones. Positive diameters 15 mm were observed in 29% of the vaccinated subjects and in 13% of the non vaccinated ones. The differences were significant for all diameters. The positive predictive value of the test was 36.4% for a diameter 5 mm, 37.6% for diameter 10 mm and 44.8% for diameter 15 mm. The booster effect was detected in 25.8% of the vaccinated individuals who had tested negative at first. In vaccinated individuals, no guidelines can be established to guarantee that a positive reaction is due to infection by Mycobacterium tuberculosis infection, although the likelihood of infection (increased positive predictive value) increases with diameter. It is also impossible to fix a time limit. A second skin test is needed to detect a booster effect in all vaccinated individuals whose first test is negative.

Behavioural Profiles of Brown and Sloth Bears in Captivity

PubMed Central

Quintavalle Pastorino, Giovanni; Christodoulides, Yiannis; Curone, Giulio; Pearce-Kelly, Paul; Faustini, Massimo; Albertini, Mariangela; Preziosi, Richard; Mazzola, Silvia Michela

2017-01-01

Simple Summary Animal personality research is a growing field, since understanding animal personalities has notable implications in ecology and the evolution of animal behaviours. In the current study, we tested different methods described in the literature to obtain robust individual behavioural profiles. Data collected through behavioral observations were categorised into activity budgets, space usage, and social interactions for each individual. In addition, behavioural profile questionnaires were completed by the three zoo keepers who had regular interactions with the bears. The questionnaires included 22 adjectives, which were rated on a scale of 1–12 depending on how well they described each individual bear. The mean ratings of the keepers were used to create the behavioural profiles by adding the adjectives to the appropriate domains, according to the NEO Five Factor Inventory of personality model (NEO-FFI). The data gathered was used to produce behavioural profiles for all animals, in order to clarify the personality characteristics of each subject. Testing and improving existing methodologies to determine animal personality is important for providing optimal welfare and management of captive animals, since it can help to develop more effective management regimes in zoos by remodelling husbandry according to each animal’s personality type. Abstract Three brown bear (Ursus arctos arctos) individuals and two sloth bear (Melursus ursinus inornatus) individuals were observed in captivity to produce behavioural profiles for each individual. Data collected through behavioural observations were used to produce activity budgets, and to identify space usage and certain aspects of social behavior. Behaviour monitoring allowed the researchers to evaluate the welfare of the animals by identifying the occurrence of stereotypic behaviours, which are sometimes associated with stress. Behavioural profiles were created using data obtained through behavioural observations (coding) and keeper questionnaires (rating). The behavioural observations indicated a number of stereotypic behaviours in sloth bears but not in brown bears. The uniformity of zone usage was calculated to investigate if the enclosure size and features were adequate for use, and a social aspect of otherwise solitary animals was also identified. The behavioural profiles generated through coding and rating were compared to determine the reliability between these two methods in Ursids. Profiles were not compared between individuals since this study is not a comparison between different personality types but rather an effort (one of the few ones existing in literature) to select a valid and reproducible methodology capable of assessing personality in bears. PMID:28505095

Counting to ten milliseconds: low-anger, but not high-anger, individuals pause following negative evaluations.

PubMed

Robinson, Michael D; Wilkowski, Benjamin M; Meier, Brian P; Moeller, Sara K; Fetterman, Adam K

2012-01-01

Low-anger individuals are less reactive, both emotionally and behaviourally, to a large variety of situational primes to anger and aggression. Why this is so, from an affective processing perspective, has been largely conjectural. Four studies (total N=270) sought to link individual differences in anger to tendencies exhibited in basic affective processing tasks. On the basis of motivational factors and considerations, it was hypothesised that negative evaluations would differentially activate a psychological alarm system at low levels of anger, resulting in a pause that should be evident in the speed of making subsequent evaluations. Just such a pattern was evident in all studies. By contrast, high-anger individuals did not pause following their negative evaluations. In relation to this affective processing tendency, at least, dramatically different effects were observed among low- versus high-anger individuals. Implications for the personality-processing literature, theories of trait anger, and fast-acting regulatory processes are discussed.

Distraction control processes in free recall: benefits and costs to performance.

PubMed

Marsh, John E; Sörqvist, Patrik; Hodgetts, Helen M; Beaman, C Philip; Jones, Dylan M

2015-01-01

How is semantic memory influenced by individual differences under conditions of distraction? This question was addressed by observing how participants recalled visual target words--drawn from a single category--while ignoring spoken distractor words that were members of either the same or a different (single) category. Working memory capacity (WMC) was related to disruption only with synchronous, not asynchronous, presentation, and distraction was greater when the words were presented synchronously. Subsequent experiments found greater negative priming of distractors among individuals with higher WMC, but this may be dependent on targets and distractors being comparable category exemplars. With less dominant category members as distractors, target recall was impaired--relative to control--only among individuals with low WMC. The results highlight the role of cognitive control resources in target-distractor selection and the individual-specific cost implications of such cognitive control. PsycINFO Database Record (c) 2015 APA, all rights reserved.

Evidence of bias affecting the interpretation of the results of local anaesthetic nerve blocks when assessing lameness in horses.

PubMed

Arkell, M; Archer, R M; Guitian, F J; May, S A

2006-09-09

Eighteen observers were influenced to different extents in the grades of lameness they allocated to eight horses by whether they knew that a nerve block had been administered; on a scale from 0 to 10 the mean difference in grade allocated once the observer knew a horse had been nerve-blocked was increased by 0.4. The consistency of the assessments made by the individual observers was good, with a an average of 0.6 of a grade difference when grading the same horse on two occasions. The agreement between the assessments of four orthopaedic experts was reasonable (+/-1 grade), but significantly poorer for four non-experts and 10 final year veterinary students.

Visual selective attention is equally functional for individuals with low and high working memory capacity: evidence from accuracy and eye movements.

PubMed

Mall, Jonathan T; Morey, Candice C; Wolff, Michael J; Lehnert, Franziska

2014-10-01

Selective attention and working memory capacity (WMC) are related constructs, but debate about the manner in which they are related remains active. One elegant explanation of variance in WMC is that the efficiency of filtering irrelevant information is the crucial determining factor, rather than differences in capacity per se. We examined this hypothesis by relating WMC (as measured by complex span tasks) to accuracy and eye movements during visual change detection tasks with different degrees of attentional filtering and allocation requirements. Our results did not indicate strong filtering differences between high- and low-WMC groups, and where differences were observed, they were counter to those predicted by the strongest attentional filtering hypothesis. Bayes factors indicated evidence favoring positive or null relationships between WMC and correct responses to unemphasized information, as well as between WMC and the time spent looking at unemphasized information. These findings are consistent with the hypothesis that individual differences in storage capacity, not only filtering efficiency, underlie individual differences in working memory.

Characterizing individual scattering events by measuring the amplitude and phase of the electric field diffusing through a random medium.

PubMed

Jian, Zhongping; Pearce, Jeremy; Mittleman, Daniel M

2003-07-18

We describe observations of the amplitude and phase of an electric field diffusing through a three-dimensional random medium, using terahertz time-domain spectroscopy. These measurements are spatially resolved with a resolution smaller than the speckle spot size and temporally resolved with a resolution better than one optical cycle. By computing correlation functions between fields measured at different positions and with different temporal delays, it is possible to obtain information about individual scattering events experienced by the diffusing field. This represents a new method for characterizing a multiply scattered wave.

An empirical examination of subjective age in older adults.

PubMed

Agogo, David; Hajjat, Fatima; Milne, George R; Schewe, Charles D; Perrott, Bruce

2017-01-01

It has been observed that subjective age (SA) often trails chronological age, especially in older adults. In a previously published article, we argued that differences in individual's SA is a function of their level of activity on biological, mental, and social dimensions. This article empirically tests this proposition using a newly created Subjective Aging Index (SAI). The SAI is related to SA above the effect of age with differences existing across age groups and sex. The findings contribute to the literature on successful aging strategies with important implications for health care practitioners, marketers, and individuals heading towards older adult years.

Adolescent cortical thickness pre- and post marijuana and alcohol initiation.

PubMed

Jacobus, Joanna; Castro, Norma; Squeglia, Lindsay M; Meloy, M J; Brumback, Ty; Huestis, Marilyn A; Tapert, Susan F

Cortical thickness abnormalities have been identified in youth using both alcohol and marijuana. However, limited studies have followed individuals pre- and post initiation of alcohol and marijuana use to help identify to what extent discrepancies in structural brain integrity are pre-existing or substance-related. Adolescents (N=69) were followed from ages 13 (pre-initiation of substance use, baseline) to ages 19 (post-initiation, follow-up). Three subgroups were identified, participants that initiated alcohol use (ALC, n=23, >20 alcohol use episodes), those that initiated both alcohol and marijuana use (ALC+MJ, n=23, >50 marijuana use episodes) and individuals that did not initiate either substance regularly by follow-up (CON, n=23, <3 alcohol use episodes, no marijuana use episodes). All adolescents underwent neurocognitive testing, neuroimaging, and substance use and mental health interviews. Significant group by time interactions and main effects on cortical thickness estimates were identified for 18 cortical regions spanning the left and right hemisphere (ps<0.05). The vast majority of findings suggest a more substantial decrease, or within-subjects effect, in cortical thickness by follow-up for individuals who have not initiated regular substance use or alcohol use only by age 19; modest between-group differences were identified at baseline in several cortical regions (ALC and CON>ALC+MJ). Minimal neurocognitive differences were observed in this sample. Findings suggest pre-existing neural differences prior to marijuana use may contribute to initiation of use and observed neural outcomes. Marijuana use may also interfere with thinning trajectories that contribute to morphological differences in young adulthood that are often observed in cross-sectional studies of heavy marijuana users. Copyright © 2016 Elsevier Inc. All rights reserved.

Understanding differences in results from literature-based and individual patient meta-analyses: an example from meta-analyses of observational data.

PubMed

Poppe, Katrina K; Doughty, Robert N; Yu, Cheuk-Man; Quintana, Miguel; Møller, Jacob E; Klein, Allan L; Gamble, Greg D; Dini, Frank L; Whalley, Gillian A

2011-04-14

Meta-analyses are increasingly used to summarise observational data however a literature meta-analysis (LMA) may give different results to the corresponding individual patient meta-analysis (IPMA). This study compares the published results of equivalent LMAs and IPMAs, highlighting factors that can affect the results and therefore impact on clinical interpretation of meta-analyses. Univariate results from published meta-analyses of prospective observational outcome data were compared, as were the number of studies, patients and length of follow-up. The absolute difference in survival was calculated. The association between severe diastolic dysfunction (RFP) and death post acute myocardial infarction (AMI) and in chronic heart failure (HF) were used as clinical examples. The IPMA hazard ratio was lower that the LMA odds ratio: AMI hazard ratio 2.67 (95% confidence interval 2.23 to 3.20), odds ratio 4.10 (3.38 to 4.99); HF hazard ratio 2.42 (2.06 to 2.83), odds ratio 4.36 (3.60 to 5.04). The IPMAs contained most of the studies from the LMAs as well as additional unpublished data, and a longer length of follow-up was available in the IPMAs (AMI 3.7 vs 2.6 yr, HF 4.0 vs 1.5 yr). Restricting analysis to the same studies in both the LMA and IPMA resulted in a similar difference in effect sizes between methods to those found in the published analyses. The result of a meta-analysis is affected by whether study level or individual patient data have been used, and the variant of analysis that is required. Awareness and consideration of these factors is important for clinical interpretation of meta-analyses. Copyright © 2009 Elsevier B.V. All rights reserved.

Adolescent Cortical Thickness Pre- and Post Marijuana and Alcohol Initiation

PubMed Central

Jacobus, Joanna; Castro, Norma; Squeglia, Lindsay M.; Meloy, M.J.; Brumback, Ty; Huestis, Marilyn; Tapert, Susan F.

2016-01-01

Cortical thickness abnormalities have been identified in youth using both alcohol and marijuana. However, limited studies have followed individuals pre- and post initiation of alcohol and marijuana use to help identify to what extent discrepancies in structural brain integrity are pre-existing or substance-related. Adolescents (N=69) were followed from ages 13 (pre-initiation of substance use, baseline) to ages 19 (post-initiation, follow-up). Three subgroups were identified, participants that initiated alcohol use (ALC, n=23, >20 alcohol use episodes), those that initiated both alcohol and marijuana use (ALC+MJ, n=23, >50 marijuana use episodes) and individuals that did not initiate either substance regularly by follow-up (CON, n=23, <3 alcohol use episodes, no marijuana use episodes). All adolescents underwent neurocognitive testing, neuroimaging, and substance use and mental health interviews. Significant group by time interactions and main effects on cortical thickness estimates were identified for 18 cortical regions spanning the left and right hemisphere (ps<.05). The vast majority of findings suggest a more substantial decrease, or within-subjects effect, in cortical thickness by follow-up for individuals who have not initiated regular substance use or alcohol use only by age 19; modest between-group differences were identified at baseline in several cortical regions (ALC and CON>ALC+MJ). Minimal neurocognitive differences were observed in this sample. Findings suggest pre-existing neural differences prior to marijuana use may contribute to initiation of use and observed neural outcomes. Marijuana use may also interfere with thinning trajectories that contribute to morphological differences in young adulthood that are often observed in cross-sectional studies of heavy marijuana users. PMID:27687470

Microfluidic Cultivation and Laser Tweezers Raman Spectroscopy of E. coli under Antibiotic Stress

PubMed Central

Pilát, Zdeněk; Bernatová, Silvie; Ježek, Jan; Kirchhoff, Johanna; Tannert, Astrid; Samek, Ota; Zemánek, Pavel

2018-01-01

Analyzing the cells in various body fluids can greatly deepen the understanding of the mechanisms governing the cellular physiology. Due to the variability of physiological and metabolic states, it is important to be able to perform such studies on individual cells. Therefore, we developed an optofluidic system in which we precisely manipulated and monitored individual cells of Escherichia coli. We tested optical micromanipulation in a microfluidic chamber chip by transferring individual bacteria into the chambers. We then subjected the cells in the chambers to antibiotic cefotaxime and we observed the changes by using time-lapse microscopy. Separately, we used laser tweezers Raman spectroscopy (LTRS) in a different micro-chamber chip to manipulate and analyze individual cefotaxime-treated E. coli cells. Additionally, we performed conventional Raman micro-spectroscopic measurements of E. coli cells in a micro-chamber. We found observable changes in the cellular morphology (cell elongation) and in Raman spectra, which were consistent with other recently published observations. The principal component analysis (PCA) of Raman data distinguished between the cefotaxime treated cells and control. We tested the capabilities of the optofluidic system and found it to be a reliable and versatile solution for this class of microbiological experiments. PMID:29783713

Individual differences in the forced swimming test and the effect of environmental enrichment: searching for an interaction.

PubMed

Sequeira-Cordero, A; Mora-Gallegos, A; Cuenca-Berger, P; Fornaguera-Trías, J

2014-04-18

Animals with low and high immobility in the forced swimming test (FST) differ in a number of neurobehavioral factors. A growing body of evidence suggests that the exposure to enriched environments mediates a number of changes in the brain. Therefore, we studied if animals' individuality can somehow modulate the response to environmental stimuli. Male rats were classified according to their immobility time scores in the FST test session as animals with low, medium or high immobility. Then, rats from groups with low and high immobility were randomly distributed in two groups to be reared in different housing conditions (i.e., enriched and standard conditions) during 8weeks. Animals were subjected to the open field test (OFT) before and 6weeks after the start of housing protocol. Rats with high immobility in the FST also showed high ambulation and high rearing time in the first OFT. Such findings were not observed in the second OFT. Conversely, an effect of environmental enrichment was found in the second OFT where enriched animals showed lower ambulation and higher grooming time than the standard control group. Rats were sacrificed after the housing protocol and neurochemical content and/or gene expression were studied in three different brain regions: the prefrontal cortex, the hippocampus and the nucleus accumbens. Rats with low immobility showed significantly higher accumbal 5-HT levels than animals with high immobility, whereas no neurochemical differences were observed between enriched and standard animals. Regarding expression data, however, an effect of enrichment on accumbal corticotropin-releasing factor (CRF) and its receptor 1 (CRFR1) levels was observed, and such effect depended on immobility levels. Thus, our results not only allowed us to identify a number of differences between animals with low and high immobility or animals housed in standard and enriched conditions, but also suggested that animals' individuality modulated in some way the response to environmental stimuli. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

Determination of several families of phytochemicals in different pre-cooked convenience vegetables: effect of lifetime and cooking.

PubMed

Alarcón-Flores, M Isabel; Hernández-Sánchez, Francisco; Romero-González, Roberto; Plaza-Bolaños, Patricia; Martínez Vidal, J Luis; Garrido Frenich, Antonia

2014-11-01

Phytochemicals content, including several families such as phenolic acids, isoflavones, flavones, flavonols, isothiocyanates, and glucosinolates, was determined in pre-cooked convenience vegetables by ultra high performance liquid chromatography coupled to triple quadrupole tandem mass spectrometry (UHPLC-QqQ-MS/MS). It was observed that there is not a common behavior of the individual concentration of phytochemicals during the lifetime and cooking of the matrix, and compounds change their concentration without a specific trend. It was observed that neither lifetime nor cooking process have significant effects on the total content of phytochemicals except in broccoli, although some changes in the individual content of the target compounds were observed, suggesting that interconversion processes could be performed during the lifetime and/or cooking process of the product.

Individual differences in Affective Neuroscience Personality Scale (ANPS) primary emotional traits and depressive tendencies.

PubMed

Montag, Christian; Widenhorn-Müller, Katharina; Panksepp, Jaak; Kiefer, Markus

2017-02-01

The present study investigated individual differences in the Affective Neuroscience Personality Scales (ANPS), representing measures of primary emotional systems, and depressive tendencies in two independent samples. In order to be able to find support for a continuum model with respect to the relation of strength in the cross-species "affective neuroscience" taxonomy of primary emotional systems, we investigated ANPS measured personality traits in a psychologically mostly healthy population (n=614 participants) as well as a sample of clinically depressed people (n=55 depressed patients). In both normal and depressed samples robust associations appeared between higher FEAR and SADNESS scores and depressive tendencies. A similar - albeit weaker - association was observed with lower SEEKING system scores and higher depressive tendencies, an effect again seen in both samples. The study is of cross-sectional nature and therefore only associations between primary emotional systems and depressive tendencies were evaluated. These results show that similar associations between ANPS monitored primary emotional systems and tendencies toward depression can be observed in both healthy and depressed participants. This lends support for a continuum of affective changes accompanying depression, potentially reflecting differences in specific brain emotional system activities in both affectively normal as well as clinically depressed individuals. Copyright © 2016 Elsevier Inc. All rights reserved.

Effects of experimental long-term CO2 exposure on Daphnia magna (Straus 1820): From physiological effects to ecological consequences.

PubMed

Parra, Gema; Galotti, Andréa; Jiménez-Melero, Raquel; Guerrero, Francisco; Sánchez-Moyano, Emilio; Jiménez-Gómez, Francisco; Conradi, Mercedes

2016-08-01

The carbon capture and storage (CCS) technologies that were proposed to mitigate environmental problems arising from anthropogenic CO2 emissions, also have potential environmental risks. An eventual CCS leak might induce very low pH values in the aquatic system. Due to the lack of knowledge of long-term CO2 exposures with very low pH values, this study aims to know the effects and consequences of such a situation for zooplankton, using the Daphnia magna experimental model. A CO2 injection system was used to provide the experimental condition. A twenty-one days experiment with control and low pH treatment (pH = 7) replicates was carried out under light and temperature-controlled conditions. Survival, individual growth, RNA:DNA ratio, and neonates production were analysed during the aforementioned period. No differences on survival (except last day), individual growth and RNA:DNA ratio were observed between both control and low pH treatments. However, clear differences were detected in neonates production and, consequently, in population growth rates and secondary production. The observed differences could be related with an energy allocation strategy to ensure individual survival but would have ecological consequences affecting higher trophic levels. Copyright © 2016 Elsevier Ltd. All rights reserved.

A comparative analysis of Patient-Reported Expanded Disability Status Scale tools.

PubMed

Collins, Christian DE; Ivry, Ben; Bowen, James D; Cheng, Eric M; Dobson, Ruth; Goodin, Douglas S; Lechner-Scott, Jeannette; Kappos, Ludwig; Galea, Ian

2016-09-01

Patient-Reported Expanded Disability Status Scale (PREDSS) tools are an attractive alternative to the Expanded Disability Status Scale (EDSS) during long term or geographically challenging studies, or in pressured clinical service environments. Because the studies reporting these tools have used different metrics to compare the PREDSS and EDSS, we undertook an individual patient data level analysis of all available tools. Spearman's rho and the Bland-Altman method were used to assess correlation and agreement respectively. A systematic search for validated PREDSS tools covering the full EDSS range identified eight such tools. Individual patient data were available for five PREDSS tools. Excellent correlation was observed between EDSS and PREDSS with all tools. A higher level of agreement was observed with increasing levels of disability. In all tools, the 95% limits of agreement were greater than the minimum EDSS difference considered to be clinically significant. However, the intra-class coefficient was greater than that reported for EDSS raters of mixed seniority. The visual functional system was identified as the most significant predictor of the PREDSS-EDSS difference. This analysis will (1) enable researchers and service providers to make an informed choice of PREDSS tool, depending on their individual requirements, and (2) facilitate improvement of current PREDSS tools. © The Author(s), 2015.

Structural and resting-state MRI detects regional brain differences in young and mid-age healthy APOE-e4 carriers compared with non-APOE-e4 carriers.

PubMed

Dowell, Nicholas G; Evans, Simon L; Tofts, Paul S; King, Sarah L; Tabet, Naji; Rusted, Jennifer M

2016-05-01

The presence of the e4 allele of the apolipoprotein E (APOE) gene is the best-known genetic risk factor for Alzheimer's disease. In this study, we investigated the link between functional and behavioural differences and regional brain volume and cortical thickness differences in those who carry the e4 allele (e4+) and those who only carry the e3 allele (e3/e3). We studied these genotype populations in two age groups: a young group (average age, 21 years) and a mid-age group (average age, 50 years). High-resolution T1 -weighted MRI scans were analysed with Freesurfer to measure regional white matter brain volume and cortical thickness differences between genotype groups at each age. These data were correlated with behavioural findings in the same cohort. Resting-state MRI was also conducted to identify differences in underlying brain functional connectivity. We found that there was a positive correlation between the thickness of the parahippocampal cortex in young e4+ individuals and performance on an episodic memory task. Young e4+ individuals also showed a positive correlation between white matter volume in the left anterior cingulate and performance on a covert attention task. At mid-age, e4+ individuals had structural differences relative to e3/e3 individuals in these areas: the parahippocampal cortex was thicker and white matter volume in the left anterior cingulate was greater than in e3/e3 individuals. We discuss the possibility that an over-engagement with these regions by e4+ individuals in youth may have a neurogenic effect that is observable later in life. The cuneus appears to be an important region for APOE-driven differences in the brain, with greater functional connectivity among young e3/e3 individuals and greater white matter volume in young e4+ individuals. Copyright © 2016 John Wiley & Sons, Ltd.

Visual perspective in autobiographical memories: reliability, consistency, and relationship to objective memory performance.

PubMed

Siedlecki, Karen L

2015-01-01

Visual perspective in autobiographical memories was examined in terms of reliability, consistency, and relationship to objective memory performance in a sample of 99 individuals. Autobiographical memories may be recalled from two visual perspectives--a field perspective in which individuals experience the memory through their own eyes, or an observer perspective in which individuals experience the memory from the viewpoint of an observer in which they can see themselves. Participants recalled nine word-cued memories that differed in emotional valence (positive, negative and neutral) and rated their memories on 18 scales. Results indicate that visual perspective was the most reliable memory characteristic overall and is consistently related to emotional intensity at the time of recall and amount of emotion experienced during the memory. Visual perspective is unrelated to memory for words, stories, abstract line drawings or faces.

Does human body odor represent a significant and rewarding social signal to individuals high in social openness?

PubMed

Lübke, Katrin T; Croy, Ilona; Hoenen, Matthias; Gerber, Johannes; Pause, Bettina M; Hummel, Thomas

2014-01-01

Across a wide variety of domains, experts differ from novices in their response to stimuli linked to their respective field of expertise. It is currently unknown whether similar patterns can be observed with regard to social expertise. The current study therefore focuses on social openness, a central social skill necessary to initiate social contact. Human body odors were used as social cues, as they inherently signal the presence of another human being. Using functional MRI, hemodynamic brain responses to body odors of women reporting a high (n = 14) or a low (n = 12) level of social openness were compared. Greater activation within the inferior frontal gyrus and the caudate nucleus was observed in high socially open individuals compared to individuals low in social openness. With the inferior frontal gyrus being a crucial part of the human mirror neuron system, and the caudate nucleus being implicated in social reward, it is discussed whether human body odor might constitute more of a significant and rewarding social signal to individuals high in social openness compared to individuals low in social openness process.

Individual differences on immunostimulatory activity of raw and black garlic extract in human primary immune cells.

PubMed

Purev, Uranchimeg; Chung, Mi Ja; Oh, Deog-Hwan

2012-08-01

The immunostimulatory activities of garlic extract using a cell line or animal models have been reported; however, no previous studies have evaluated individual differences in regards to the immunostimulatory activities. The immunostimulatory activities such as cell proliferation, tumor necrosis factor (TNF-α) and nitric oxides (NO) production of raw garlic and black garlic extracts on individual primary lymphocytes or macrophages isolated from the blood of 21 volunteers were evaluated. The antioxidant and anticancer effects of raw garlic and black garlic ethanol extract was measured to determine the optimum conditions for extraction. The 70% ethanol black garlic extracts at 70°C for 12 h (70% BGE) showed the strongest antioxidant and anticancer activities. Immunostimulatory activities of garlic extracts extracted under optimal condition on primary immune cells obtained from 21 volunteers were analyzed. Results showed that the cell proliferation, TNF-α and NO production of primary immune cells treated with 70% raw garlic extract (70% RGE) were significantly different; however, little difference was observed for the 70% BGE treatment. BGE showed stronger immunostimulatory activities than RGE. These results indicate that the immunostimulatory activities of RGE and BGE can be strongly correlated with the antioxidant and anticancer activities. Determination of immunostimulatory activities of different types of garlic using immune cells isolated from volunteers was dependent on the individual constituents due to changes in the composition of garlic during processing. Individual primary immune cells might be used as important tools to determine individual differences in all food ingredients for the development of personalized immunostimulatory active foods.

Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects

PubMed Central

Smith, Matthew J.; Cobia, Derin J.; Reilly, James L.; Gilman, Jodi; Roberts, Andrea G.; Alpert, Kathryn I.; Wang, Lei; Breiter, Hans C.; Csernansky, John G.

2015-01-01

Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large- deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ- CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM. Shape differences observed in CON-CUD were associated with poorer EM, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD abstinence. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis. PMID:25760303

Regulatory T-Cell Distribution within Lung Compartments in COPD.

PubMed

Sales, Davi S; Ito, Juliana T; Zanchetta, Ivy A; Annoni, Raquel; Aun, Marcelo V; Ferraz, Luiz Fernando S; Cervilha, Daniela A B; Negri, Elnara; Mauad, Thais; Martins, Mílton A; Lopes, Fernanda D T Q S

2017-10-01

The importance of the adaptive immune response, specifically the role of regulatory T (Treg) cells in controlling the obstruction progression in smokers, has been highlighted. To quantify the adaptive immune cells in different lung compartments, we used lung tissues from 21 never-smokers without lung disease, 22 current and/or ex-smokers without lung disease (NOS) and 13 current and/or ex-smokers with chronic obstructive pulmonary disease (COPD) for histological analysis. We observed increased T, B, IL-17 and BAFF + cells in small and large airways of COPD individuals; however, in the NOS, we only observed increase in T and IL-17 + cells only in small airways. A decrease in the density of Treg + , TGF-β + and IL-10 + in small and large airways was observed only in COPD individuals. In the lymphoid tissues, Treg, T,B-cells and BAFF + cells were also increased in COPD; however, changes in Treg inhibitory associated cytokines were not observed in this compartment. Therefore, our results suggest that difference in Treg + cell distributions in lung compartments and the decrease in TGF-β + and IL-10 + cells in the airways may lead to the obstruction in smokers.

Knowing what from where: Hippocampal connectivity with temporoparietal cortex at rest is linked to individual differences in semantic and topographic memory.

PubMed

Sormaz, Mladen; Jefferies, Elizabeth; Bernhardt, Boris C; Karapanagiotidis, Theodoros; Mollo, Giovanna; Bernasconi, Neda; Bernasconi, Andrea; Hartley, Tom; Smallwood, Jonathan

2017-05-15

The hippocampus contributes to episodic, spatial and semantic aspects of memory, yet individual differences within and between these functions are not well-understood. In 136 healthy individuals, we investigated whether these differences reflect variation in the strength of connections between functionally-specialised segments of the hippocampus and diverse cortical regions that participate in different aspects of memory. Better topographical memory was associated with stronger connectivity between lingual gyrus and left anterior, rather than posterior, hippocampus. Better semantic memory was associated with increased connectivity between the intracalcarine/cuneus and left, rather than right, posterior hippocampus. Notably, we observed a double dissociation between semantic and topographical memory: better semantic memory was associated with stronger connectivity between left temporoparietal cortex and left anterior hippocampus, while better topographic memory was linked to stronger connectivity with right anterior hippocampus. Together these data support a division-of-labour account of hippocampal functioning: at the population level, differences in connectivity across the hippocampus reflect functional specialisation for different facets of memory, while variation in these connectivity patterns across individuals is associated with differences in the capacity to retrieve different types of information. In particular, within-hemisphere connectivity between hippocampus and left temporoparietal cortex supports conceptual processing at the expense of spatial ability. Copyright © 2017. Published by Elsevier Inc.

Differences in physical fitness and throwing velocity among elite and amateur male handball players.

PubMed

Gorostiaga, E M; Granados, C; Ibáñez, J; Izquierdo, M

2005-04-01

This study compared physical characteristics (body height, body mass [BM], body fat [BF], and free fatty mass [FFM]), one repetition maximum bench-press (1RM (BP)), jumping explosive strength (VJ), handball throwing velocity, power-load relationship of the leg and arm extensor muscles, 5- and 15-m sprint running time, and running endurance in two handball male teams: elite team, one of the world's leading teams (EM, n = 15) and amateur team, playing in the Spanish National Second Division (AM, n = 15). EM had similar values in body height, BF, VJ, 5- and 15-m sprint running time and running endurance than AM. However, the EM group gave higher values in BM (95.2 +/- 13 kg vs. 82.4 +/- 10 kg, p < 0.05), FFM (81.7 +/- 9 kg vs. 72.4 +/- 7 kg, p < 0.05), 1RM (BP) (107 +/- 12 kg vs. 83 +/- 10 kg, p < 0.001), muscle power during bench-press (18 - 21 %, p < 0.05) and half squat (13 - 17 %), and throwing velocities at standing (23.8 +/- 1.9 m . s (-1) vs. 21.8 +/- 1.6 m . s (-1), p < 0.05) and 3-step running (25.3 +/- 2.2 m . s (-1) vs. 22.9 +/- 1.4 m . s (-1), p < 0.05) actions than the AM group. Significant correlations (r = 0.67 - 0.71, p < 0.05 - 0.01) were observed in EM and AM between individual values of velocity at 30 % of 1RM (BP) and individual values of ball velocity during a standing throw. Significant correlations were observed in EM, but not in AM, between the individual values of velocity during 3-step running throw and the individual values of velocity at 30 % of 1RM (BP) (r = 0.72, p < 0.05), as well as the individual values of power at 100 % of body mass during half-squat actions (r = 0.62, p < 0.05). The present results suggest that more muscular and powerful players are at an advantage in handball. The differences observed in free fatty mass could partly explain the differences observed between groups in absolute maximal strength and muscle power. In EM, higher efficiency in handball throwing velocity may be associated with both upper and lower extremity power output capabilities, whereas in AM this relationship may be different. Endurance capacity does not seem to represent a limitation for elite performance in handball.

ISCCP Cloud Properties Associated with Standard Cloud Types Identified in Individual Surface Observations

NASA Technical Reports Server (NTRS)

Hahn, Carole J.; Rossow, William B.; Warren, Stephen G.

1999-01-01

Individual surface weather observations from land stations and ships are compared with individual cloud retrievals of the International Satellite Cloud Climatology Project (ISCCP), Stage C1, for an 8-year period (1983-1991) to relate cloud optical thicknesses and cloud-top pressures obtained from satellite data to the standard cloud types reported in visual observations from the surface. Each surface report is matched to the corresponding ISCCP-C1 report for the time of observation for the 280x280-km grid-box containing that observation. Classes of the surface reports are identified in which a particular cloud type was reported present, either alone or in combination with other clouds. For each class, cloud amounts from both surface and C1 data, base heights from surface data, and the frequency-distributions of cloud-top pressure (p(sub c) and optical thickness (tau) from C1 data are averaged over 15-degree latitude zones, for land and ocean separately, for 3-month seasons. The frequency distribution of p(sub c) and tau is plotted for each of the surface-defined cloud types occurring both alone and with other clouds. The average cloud-top pressures within a grid-box do not always correspond well with values expected for a reported cloud type, particularly for the higher clouds Ci, Ac, and Cb. In many cases this is because the satellites also detect clouds within the grid-box that are outside the field of view of the surface observer. The highest average cloud tops are found for the most extensive cloud type, Ns, averaging 7 km globally and reaching 9 km in the ITCZ. Ns also has the greatest average retrieved optical thickness, tau approximately equal 20. Cumulonimbus clouds may actually attain far greater heights and depths, but do not fill the grid-box. The tau-p(sub c) distributions show features that distinguish the high, middle, and low clouds reported by the surface observers. However, the distribution patterns for the individual low cloud types (Cu, Sc, St) occurring alone overlap to such an extent that it is not possible to distinguish these cloud types from each other on the basis of tau-p(sub c) values alone. Other cloud types whose tau-p(sub c) distributions are indistinguishable are Cb, Ns, and thick As. However, the tau-p(sub c) distribution patterns for the different low cloud types are nevertheless distinguishable when all occurrences of a low cloud type are included, indicating that the different low types differ in their probabilities of co-occurrence with middle and high clouds.

Individual specialization in the foraging habits of female bottlenose dolphins living in a trophically diverse and habitat rich estuary

USGS Publications Warehouse

Rossman, Sam; Ostrom, Peggy H.; Stolen, Megan; Barros, Nélio B.; Gandhi, Hasand; Stricker, Craig A.; Wells, Randall S.

2015-01-01

We examine individual specialization in foraging habits (foraging habitat and trophic level) of female bottlenose dolphins (Tursiops truncatus) resident in Sarasota Bay, Florida, USA, by analyzing time series of stable isotope (δ15N and δ13C) values in sequential growth layer groups within teeth. The isotope data provide a chronology of foraging habits over the lifetime of the individual and allowed us to show that female bottlenose dolphins exhibit a high degree of individual specialization in both foraging habitat and trophic level. The foraging habits used by adult females are similar to those they used as calves and may be passed down from mother to calf through social learning. We also characterized the foraging habits and home range of each individual by constructing standard ellipses from isotope values and dolphin sightings data (latitude and longitude), respectively. These data show that Sarasota Bay bottlenose dolphins forage within a subset of the habitats in which they are observed. Moreover, females with similar observational standard ellipses often possessed different foraging specializations. Female bottlenose dolphins may demonstrate individual specialization in foraging habits because it reduces some of the cost of living in groups, such as competition for prey.

Does resting-state connectivity reflect depressive rumination? A tale of two analyses.

PubMed

Berman, Marc G; Misic, Bratislav; Buschkuehl, Martin; Kross, Ethan; Deldin, Patricia J; Peltier, Scott; Churchill, Nathan W; Jaeggi, Susanne M; Vakorin, Vasily; McIntosh, Anthony R; Jonides, John

2014-12-01

Major Depressive Disorder (MDD) is characterized by rumination. Prior research suggests that resting-state brain activation reflects rumination when depressed individuals are not task engaged. However, no study has directly tested this. Here we investigated whether resting-state epochs differ from induced ruminative states for healthy and depressed individuals. Most previous research on resting-state networks comes from seed-based analyses with the posterior cingulate cortex (PCC). By contrast, we examined resting state connectivity by using the complete multivariate connectivity profile (i.e., connections across all brain nodes) and by comparing these results to seeded analyses. We find that unconstrained resting-state intervals differ from active rumination states in strength of connectivity and that overall connectivity was higher for healthy vs. depressed individuals. Relationships between connectivity and subjective mood (i.e., behavior) were strongly observed during induced rumination epochs. Furthermore, connectivity patterns that related to subjective mood were strikingly different for MDD and healthy control (HC) groups suggesting different mood regulation mechanisms. Copyright © 2014 Elsevier Inc. All rights reserved.

Error-Monitoring in Response to Social Stimuli in Individuals with Higher-Functioning Autism Spectrum Disorder

PubMed Central

McMahon, Camilla M.; Henderson, Heather A.

2014-01-01

Error-monitoring, or the ability to recognize one's mistakes and implement behavioral changes to prevent further mistakes, may be impaired in individuals with Autism Spectrum Disorder (ASD). Children and adolescents (ages 9-19) with ASD (n = 42) and typical development (n = 42) completed two face processing tasks that required discrimination of either the gender or affect of standardized face stimuli. Post-error slowing and the difference in Error-Related Negativity amplitude between correct and incorrect responses (ERNdiff) were used to index error-monitoring ability. Overall, ERNdiff increased with age. On the Gender Task, individuals with ASD had a smaller ERNdiff than individuals with typical development; however, on the Affect Task, there were no significant diagnostic group differences on ERNdiff. Individuals with ASD may have ERN amplitudes similar to those observed in individuals with typical development in more social contexts compared to less social contexts due to greater consequences for errors, more effortful processing, and/or reduced processing efficiency in these contexts. Across all participants, more post-error slowing on the Affect Task was associated with better social cognitive skills. PMID:25066088

Selected Harvesting Machines For Short Rotation Intensive Culture Biomass Plantations

Treesearch

Sammy Woodfin; Doug Frederick; Bryce Stokes

1987-01-01

Three different harvesting systems were observed and analyzed for productivity and costs in a short rotation.intensive culture plantation of 2 to 5 year old sycamore. Individual machines were compared to create an optimum system.

The Kaplan-Meier Theatre

ERIC Educational Resources Information Center

Gerds, Thomas A.

2016-01-01

Survival is difficult to estimate when observation periods of individuals differ in length. Students imagine sailing the Titanic and then recording whether they "live" or "die." A clever algorithm is performed which results in the Kaplan-Meier estimate of survival.

Music supported therapy promotes motor plasticity in individuals with chronic stroke.

PubMed

Ripollés, P; Rojo, N; Grau-Sánchez, J; Amengual, J L; Càmara, E; Marco-Pallarés, J; Juncadella, M; Vaquero, L; Rubio, F; Duarte, E; Garrido, C; Altenmüller, E; Münte, T F; Rodríguez-Fornells, A

2016-12-01

Novel rehabilitation interventions have improved motor recovery by induction of neural plasticity in individuals with stroke. Of these, Music-supported therapy (MST) is based on music training designed to restore motor deficits. Music training requires multimodal processing, involving the integration and co-operation of visual, motor, auditory, affective and cognitive systems. The main objective of this study was to assess, in a group of 20 individuals suffering from chronic stroke, the motor, cognitive, emotional and neuroplastic effects of MST. Using functional magnetic resonance imaging (fMRI) we observed a clear restitution of both activity and connectivity among auditory-motor regions of the affected hemisphere. Importantly, no differences were observed in this functional network in a healthy control group, ruling out possible confounds such as repeated imaging testing. Moreover, this increase in activity and connectivity between auditory and motor regions was accompanied by a functional improvement of the paretic hand. The present results confirm MST as a viable intervention to improve motor function in chronic stroke individuals.

Dorso-Lateral Prefrontal Cortex MRI Measurements and Cognitive Performance in Autism

PubMed Central

Griebling, Jessica; Minshew, Nancy J.; Bodner, Kimberly; Libove, Robin; Bansal, Rahul; Konasale, Prasad; Keshavan, Matcheri S.; Hardan, Antonio

2012-01-01

This study examined the relationships between volumetric measurements of frontal lobe structures and performance on executive function tasks in individuals with autism. MRI scans were obtained from 38 individuals with autism and 40 matched controls between the ages of 8 and 45 years. Executive function was assessed using neuropsychological measures including the Wisconsin Card Sorting Test and Tower of Hanoi. Differences in performance on the neuropsychological tests were found between the two groups. However, no differences in dorsolateral prefrontal cortex volumes were observed between groups. No correlations between volumetric measurements and performance on the neuropsychological tests were found. Findings from this study suggest that executive function deficits observed in autism are related to functional but not anatomical abnormalities of the frontal lobe. The absence of correlations suggests that executive dysfunction is not the result of focal brain alterations but, rather, is the result of a distributed neural network dysfunction. PMID:20097663

Dynamic response of an artificial square spin ice

DOE PAGES

Jungfleisch, M. B.; Zhang, W.; Iacocca, E.; ...

2016-03-02

Magnetization dynamics in an artficial square spin-ice lattice made of Ni80Fe20 with magnetic field applied in the lattice plane is investigated by broadband ferromagnetic resonance spectroscopy. The experimentally observed dispersion shows a rich spectrum of modes corresponding to different magnetization states. These magnetization states are determined by exchange and dipolar interaction between individual islands, as is confirmed by a semianalytical model. In the low field regime below 400 Oe a hysteretic behavior in the mode spectrum is found. Micromagnetic simulations reveal that the origin of the observed spectra is due to the initialization of different magnetization states of individual nanomagnets.more » Our results indicate that it might be possible to determine the spin-ice state by resonance experiments and are a first step towards the understanding of artificial geometrically frustrated magnetic systems in the high-frequency regime.« less

Dynamic response of an artificial square spin ice

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

Jungfleisch, M. B.; Zhang, W.; Iacocca, E.

Magnetization dynamics in an artficial square spin-ice lattice made of Ni80Fe20 with magnetic field applied in the lattice plane is investigated by broadband ferromagnetic resonance spectroscopy. The experimentally observed dispersion shows a rich spectrum of modes corresponding to different magnetization states. These magnetization states are determined by exchange and dipolar interaction between individual islands, as is confirmed by a semianalytical model. In the low field regime below 400 Oe a hysteretic behavior in the mode spectrum is found. Micromagnetic simulations reveal that the origin of the observed spectra is due to the initialization of different magnetization states of individual nanomagnets.more » Our results indicate that it might be possible to determine the spin-ice state by resonance experiments and are a first step towards the understanding of artificial geometrically frustrated magnetic systems in the high-frequency regime.« less

Individual Differences in Effectiveness of Cochlear Implants in Children Who Are Prelingually Deaf: New Process Measures of Performance

PubMed Central

Pisoni, David B.; Cleary, Miranda; Geers, Ann E.; Tobey, Emily A.

2011-01-01

The efficacy of cochlear implants in children who are deaf has been firmly established in the literature. However, the effectiveness of cochlear implants varies widely and is influenced by demographic and experiential factors. Several key findings suggest new directions for research on central auditory factors that underlie the effectiveness of cochlear implants. First, enormous individual differences have been observed in both adults and children on a wide range of audiological outcome measures. Some patients show large increases in speech perception scores after implantation, whereas others display only modest gains on standardized tests. Second, age of implantation and length of deafness affect all outcome measures. Children implanted at younger ages do better than children implanted at older ages, and children who have been deaf for shorter periods do better than children who have been deaf for longer periods. Third, communication mode affects outcome measures. Children from “oral-only” environments do much better on standardized tests that assess phonological processing skills than children who use Total Communication. Fourth, at the present time there are no preimplant predictors of outcome performance in young children. The underlying perceptual, cognitive, and linguistic abilities and skills emerge after implantation and improve over time. Finally, there are no significant differences in audiological outcome measures among current implant devices or processing strategies. This finding suggests that the major source of variance in outcome measures lies in the neural and cognitive information processing operations that the user applies to the signal provided by the implant. Taken together, this overall pattern of results suggests that higher-level central processes such as perception, attention, learning, and memory may play important roles in explaining the large individual differences observed among users of cochlear implants. Investigations of the content and flow of information in the central nervous system and interactions between sensory input and stored knowledge may provide important new insights into the basis of individual differences. Knowledge about the underlying basis of individual differences may also help in developing new intervention strategies to improve the effectiveness of cochlear implants in children who show relatively poor development of oral/aural language skills. PMID:21666760

The cost of reproduction: differential resource specialization in female and male California sea otters.

PubMed

Smith, Emma A Elliott; Newsome, Seth D; Estes, James A; Tinker, M Tim

2015-05-01

Intraspecific variation in behavior and diet can have important consequences for population and ecosystem dynamics. Here, we examine how differences in reproductive investment and spatial ecology influence individual diet specialization in male and female southern sea otters (Enhydra lutris nereis). We hypothesize that greater reproductive constraints and smaller home ranges of females lead to more pronounced intraspecific competition and increased specialization. We integrate stable carbon (δ(13)C) and nitrogen (δ(15)N) isotope analysis of sea otter vibrissae with long-term observational studies of five subpopulations in California. We define individual diet specialization as low ratios of within-individual variation (WIC) to total population niche width (TNW). We compare isotopic and observational based metrics of WIC/TNW for males and females to data on population densities, and movement patterns using both general linear and linear mixed-effects models. Consistent with our hypothesis, increasing population density is associated with increased individual diet specialization by females but not by males. Additionally, we find the amount of coastline in a sea otter's home range positively related with individual dietary variability, with increased range span resulting in weaker specialization for both males and females. We attribute our results to sex-based differences in movement, with females needing to specialize in their small ranges to maximize energy gain, and posit that the paradigm of individual prey specialization in sea otters with increased intraspecific competition may be a pattern driven largely by females. Our work highlights a potentially broader role of sex in the mechanistic pressures promoting and maintaining diet specialization.

The cost of reproduction: differential resource specialization in female and male California sea otters

USGS Publications Warehouse

Elliott Smith, Emma A.; Newsome, Seth D.; Estes, James A.; Tinker, M. Tim

2015-01-01

Intraspecific variation in behavior and diet can have important consequences for population and ecosystem dynamics. Here, we examine how differences in reproductive investment and spatial ecology influence individual diet specialization in male and female southern sea otters (Enhydra lutris nereis). We hypothesize that greater reproductive constraints and smaller home ranges of females lead to more pronounced intraspecific competition and increased specialization. We integrate stable carbon (δ13C) and nitrogen (δ15N) isotope analysis of sea otter vibrissae with long-term observational studies of five subpopulations in California. We define individual diet specialization as low ratios of within-individual variation (WIC) to total population niche width (TNW). We compare isotopic and observational based metrics of WIC/TNW for males and females to data on population densities, and movement patterns using both general linear and linear mixed-effects models. Consistent with our hypothesis, increasing population density is associated with increased individual diet specialization by females but not by males. Additionally, we find the amount of coastline in a sea otter’s home range positively related with individual dietary variability, with increased range span resulting in weaker specialization for both males and females. We attribute our results to sex-based differences in movement, with females needing to specialize in their small ranges to maximize energy gain, and posit that the paradigm of individual prey specialization in sea otters with increased intraspecific competition may be a pattern driven largely by females. Our work highlights a potentially broader role of sex in the mechanistic pressures promoting and maintaining diet specialization.

Inferring individual-level processes from population-level patterns in cultural evolution

PubMed Central

Wilder, Bryan

2017-01-01

Our species is characterized by a great degree of cultural variation, both within and between populations. Understanding how group-level patterns of culture emerge from individual-level behaviour is a long-standing question in the biological and social sciences. We develop a simulation model capturing demographic and cultural dynamics relevant to human cultural evolution, focusing on the interface between population-level patterns and individual-level processes. The model tracks the distribution of variants of cultural traits across individuals in a population over time, conditioned on different pathways for the transmission of information between individuals. From these data, we obtain theoretical expectations for a range of statistics commonly used to capture population-level characteristics (e.g. the degree of cultural diversity). Consistent with previous theoretical work, our results show that the patterns observed at the level of groups are rooted in the interplay between the transmission pathways and the age structure of the population. We also explore whether, and under what conditions, the different pathways can be distinguished based on their group-level signatures, in an effort to establish theoretical limits to inference. Our results show that the temporal dynamic of cultural change over time retains a stronger signature than the cultural composition of the population at a specific point in time. Overall, the results suggest a shift in focus from identifying the one individual-level process that likely produced the observed data to excluding those that likely did not. We conclude by discussing the implications for empirical studies of human cultural evolution. PMID:28989786

Risk and resilience factors in coping with daily stress in adulthood: the role of age, self-concept incoherence, and personal control.

PubMed

Diehl, Manfred; Hay, Elizabeth L

2010-09-01

This study observed young, middle-aged, and older adults (N = 239; Mage = 49.6 years; range = 18-89 years) for 30 consecutive days to examine the association between daily stress and negative affect, taking into account potential risk (i.e., self-concept incoherence) and resilience (i.e., age, perceived personal control) factors. Results indicated that younger individuals and individuals with a more incoherent self-concept showed higher average negative affect across the study. As well, individuals reported higher negative affect on days that they experienced more stress than usual and on days that they reported less control than usual. These main effects were qualified by significant interactions. In particular, the association between daily stress and negative affect was stronger on days on which adults reported low control compared with days on which they reported high control (i.e., perceptions of control buffered stress). Reactivity to daily stress did not differ for individuals of different ages or for individuals with different levels of self-concept incoherence. Although all individuals reported higher negative affect on days on which they reported less control than usual, this association was more pronounced among younger adults. The current study helps to elucidate the role of risk and resilience factors when adults are faced with daily stress.

High ferritin levels have major effects on the morphology of erythrocytes in Alzheimer's disease.

PubMed

Bester, Janette; Buys, Antoinette V; Lipinski, Boguslaw; Kell, Douglas B; Pretorius, Etheresia

2013-01-01

Unliganded iron both contributes to the pathology of Alzheimer's disease (AD) and also changes the morphology of erythrocytes (RBCs). We tested the hypothesis that these two facts might be linked, i.e., that the RBCs of AD individuals have a variant morphology, that might have diagnostic or prognostic value. We included a literature survey of AD and its relationships to the vascular system, followed by a laboratory study. Four different microscopy techniques were used and results statistically compared to analyze trends between high and normal serum ferritin (SF) AD individuals. Light and scanning electron microscopies showed little difference between the morphologies of RBCs taken from healthy individuals and from normal SF AD individuals. By contrast, there were substantial changes in the morphology of RBCs taken from high SF AD individuals. These differences were also observed using confocal microscopy and as a significantly greater membrane stiffness (measured using force-distance curves). We argue that high ferritin levels may contribute to an accelerated pathology in AD. Our findings reinforce the importance of (unliganded) iron in AD, and suggest the possibility both of an early diagnosis and some means of treating or slowing down the progress of this disease.

Cardiorespiratory response to exercise testing in individuals with Alzheimer's disease.

PubMed

Billinger, Sandra A; Vidoni, Eric D; Honea, Robyn A; Burns, Jeffrey M

2011-12-01

To examine exercise testing response in Alzheimer's disease (AD) and possible disease-related change over time. Retrospective assessment of a 2-year observational study. University medical center. Individuals without dementia (n=50) and with AD (n=31). Not applicable. Participants underwent a clinical dementia evaluation and performed an incremental exercise test using a treadmill and the modified Bruce protocol at baseline and at a 2-year follow-up. We examined oxygen consumption, minute ventilation, heart rate, and ventilatory equivalents for oxygen and carbon dioxide at submaximal and peak exercise intensities to determine whether the measures were different between groups or over time. Participants with AD and those without dementia performed similarly at submaximal effort, and both groups showed similar changes in exercise response over 2 years. However, nondemented individuals had consistently higher values of oxygen consumption (P≤.02) and minute ventilation at peak effort at baseline (P=.003). Individuals with AD demonstrate physiologic responses to submaximal exercise effort that are not significantly different than individuals without dementia. However, differences are apparent at the extreme of effort. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Monetary reward processing in obese individuals with and without binge eating disorder.

PubMed

Balodis, Iris M; Kober, Hedy; Worhunsky, Patrick D; White, Marney A; Stevens, Michael C; Pearlson, Godfrey D; Sinha, Rajita; Grilo, Carlos M; Potenza, Marc N

2013-05-01

An important step in obesity research involves identifying neurobiological underpinnings of nonfood reward processing unique to specific subgroups of obese individuals. Nineteen obese individuals seeking treatment for binge eating disorder (BED) were compared with 19 non-BED obese individuals (OB) and 19 lean control subjects (LC) while performing a monetary reward/loss task that parses anticipatory and outcome components during functional magnetic resonance imaging. Differences in regional activation were investigated in BED, OB, and LC groups during reward/loss prospect, anticipation, and notification. Relative to the LC group, the OB group demonstrated increased ventral striatal and ventromedial prefrontal cortex activity during anticipatory phases. In contrast, the BED group relative to the OB group demonstrated diminished bilateral ventral striatal activity during anticipatory reward/loss processing. No differences were observed between the BED and LC groups in the ventral striatum. Heterogeneity exists among obese individuals with respect to the neural correlates of reward/loss processing. Neural differences in separable groups with obesity suggest that multiple, varying interventions might be important in optimizing prevention and treatment strategies for obesity. Copyright © 2013 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

High intraspecific variability in the functional niche of a predator is associated with ontogenetic shift and individual specialization

PubMed Central

Zhao, Tian; Villéger, Sébastien; Lek, Sovan; Cucherousset, Julien

2014-01-01

Investigations on the functional niche of organisms have primarily focused on differences among species and tended to neglect the potential effects of intraspecific variability despite the fact that its potential ecological and evolutionary importance is now widely recognized. In this study, we measured the distribution of functional traits in an entire population of largemouth bass (Micropterus salmoides) to quantify the magnitude of intraspecific variability in functional traits and niche (size, position, and overlap) between age classes. Stable isotope analyses (δ13C and δ15N) were also used to determine the association between individual trophic ecology and intraspecific functional trait variability. We observed that functional traits were highly variable within the population (mean coefficient variation: 15.62% ± 1.78% SE) and predominantly different between age classes. In addition, functional and trophic niche overlap between age classes was extremely low. Differences in functional niche between age classes were associated with strong changes in trophic niche occurring during ontogeny while, within age classes, differences among individuals were likely driven by trophic specialization. Each age class filled only a small portion of the total functional niche of the population and age classes occupied distinct portions in the functional space, indicating the existence of ontogenetic specialists with different functional roles within the population. The high amplitude of intraspecific variability in functional traits and differences in functional niche position among individuals reported here supports the recent claims for an individual-based approach in functional ecology. PMID:25558359

Neural Mechanisms Underlying Risk and Ambiguity Attitudes.

PubMed

Blankenstein, Neeltje E; Peper, Jiska S; Crone, Eveline A; van Duijvenvoorde, Anna C K

2017-11-01

Individual differences in attitudes to risk (a taste for risk, known probabilities) and ambiguity (a tolerance for uncertainty, unknown probabilities) differentially influence risky decision-making. However, it is not well understood whether risk and ambiguity are coded differently within individuals. Here, we tested whether individual differences in risk and ambiguity attitudes were reflected in distinct neural correlates during choice and outcome processing of risky and ambiguous gambles. To these ends, we developed a neuroimaging task in which participants ( n = 50) chose between a sure gain and a gamble, which was either risky or ambiguous, and presented decision outcomes (gains, no gains). From a separate task in which the amount, probability, and ambiguity level were varied, we estimated individuals' risk and ambiguity attitudes. Although there was pronounced neural overlap between risky and ambiguous gambling in a network typically related to decision-making under uncertainty, relatively more risk-seeking attitudes were associated with increased activation in valuation regions of the brain (medial and lateral OFC), whereas relatively more ambiguity-seeking attitudes were related to temporal cortex activation. In addition, although striatum activation was observed during reward processing irrespective of a prior risky or ambiguous gamble, reward processing after an ambiguous gamble resulted in enhanced dorsomedial PFC activation, possibly functioning as a general signal of uncertainty coding. These findings suggest that different neural mechanisms reflect individual differences in risk and ambiguity attitudes and that risk and ambiguity may impact overt risk-taking behavior in different ways.

Keypress-Based Musical Preference Is Both Individual and Lawful.

PubMed

Livengood, Sherri L; Sheppard, John P; Kim, Byoung W; Malthouse, Edward C; Bourne, Janet E; Barlow, Anne E; Lee, Myung J; Marin, Veronica; O'Connor, Kailyn P; Csernansky, John G; Block, Martin P; Blood, Anne J; Breiter, Hans C

2017-01-01

Musical preference is highly individualized and is an area of active study to develop methods for its quantification. Recently, preference-based behavior, associated with activity in brain reward circuitry, has been shown to follow lawful, quantifiable patterns, despite broad variation across individuals. These patterns, observed using a keypress paradigm with visual stimuli, form the basis for relative preference theory (RPT). Here, we sought to determine if such patterns extend to non-visual domains (i.e., audition) and dynamic stimuli, potentially providing a method to supplement psychometric, physiological, and neuroimaging approaches to preference quantification. For this study, we adapted our keypress paradigm to two sets of stimuli consisting of seventeenth to twenty-first century western art music (Classical) and twentieth to twenty-first century jazz and popular music (Popular). We studied a pilot sample and then a separate primary experimental sample with this paradigm, and used iterative mathematical modeling to determine if RPT relationships were observed with high R 2 fits. We further assessed the extent of heterogeneity in the rank ordering of keypress-based responses across subjects. As expected, individual rank orderings of preferences were quite heterogeneous, yet we observed mathematical patterns fitting these data similar to those observed previously with visual stimuli. These patterns in music preference were recurrent across two cohorts and two stimulus sets, and scaled between individual and group data, adhering to the requirements for lawfulness. Our findings suggest a general neuroscience framework that predicts human approach/avoidance behavior, while also allowing for individual differences and the broad diversity of human choices; the resulting framework may offer novel approaches to advancing music neuroscience, or its applications to medicine and recommendation systems.

Keypress-Based Musical Preference Is Both Individual and Lawful

PubMed Central

Livengood, Sherri L.; Sheppard, John P.; Kim, Byoung W.; Malthouse, Edward C.; Bourne, Janet E.; Barlow, Anne E.; Lee, Myung J.; Marin, Veronica; O'Connor, Kailyn P.; Csernansky, John G.; Block, Martin P.; Blood, Anne J.; Breiter, Hans C.

2017-01-01

Musical preference is highly individualized and is an area of active study to develop methods for its quantification. Recently, preference-based behavior, associated with activity in brain reward circuitry, has been shown to follow lawful, quantifiable patterns, despite broad variation across individuals. These patterns, observed using a keypress paradigm with visual stimuli, form the basis for relative preference theory (RPT). Here, we sought to determine if such patterns extend to non-visual domains (i.e., audition) and dynamic stimuli, potentially providing a method to supplement psychometric, physiological, and neuroimaging approaches to preference quantification. For this study, we adapted our keypress paradigm to two sets of stimuli consisting of seventeenth to twenty-first century western art music (Classical) and twentieth to twenty-first century jazz and popular music (Popular). We studied a pilot sample and then a separate primary experimental sample with this paradigm, and used iterative mathematical modeling to determine if RPT relationships were observed with high R2 fits. We further assessed the extent of heterogeneity in the rank ordering of keypress-based responses across subjects. As expected, individual rank orderings of preferences were quite heterogeneous, yet we observed mathematical patterns fitting these data similar to those observed previously with visual stimuli. These patterns in music preference were recurrent across two cohorts and two stimulus sets, and scaled between individual and group data, adhering to the requirements for lawfulness. Our findings suggest a general neuroscience framework that predicts human approach/avoidance behavior, while also allowing for individual differences and the broad diversity of human choices; the resulting framework may offer novel approaches to advancing music neuroscience, or its applications to medicine and recommendation systems. PMID:28512395

Action observation and mirror neuron network: a tool for motor stroke rehabilitation.

PubMed

Sale, P; Franceschini, M

2012-06-01

Mirror neurons are a specific class of neurons that are activated and discharge both during observation of the same or similar motor act performed by another individual and during the execution of a motor act. Different studies based on non invasive neuroelectrophysiological assessment or functional brain imaging techniques have demonstrated the presence of the mirror neuron and their mechanism in humans. Various authors have demonstrated that in the human these networks are activated when individuals learn motor actions via execution (as in traditional motor learning), imitation, observation (as in observational learning) and motor imagery. Activation of these brain areas (inferior parietal lobe and the ventral premotor cortex, as well as the caudal part of the inferior frontal gyrus [IFG]) following observation or motor imagery may thereby facilitate subsequent movement execution by directly matching the observed or imagined action to the internal simulation of that action. It is therefore believed that this multi-sensory action-observation system enables individuals to (re) learn impaired motor functions through the activation of these internal action-related representations. In humans, the mirror mechanism is also located in various brain segment: in Broca's area, which is involved in language processing and speech production and not only in centres that mediate voluntary movement, but also in cortical areas that mediate visceromotor emotion-related behaviours. On basis of this finding, during the last 10 years various studies were carry out regarding the clinical use of action observation for motor rehabilitation of sub-acute and chronic stroke patients.

Evolutionary model with genetics, aging, and knowledge

NASA Astrophysics Data System (ADS)

Bustillos, Armando Ticona; de Oliveira, Paulo Murilo

2004-02-01

We represent a process of learning by using bit strings, where 1 bits represent the knowledge acquired by individuals. Two ways of learning are considered: individual learning by trial and error, and social learning by copying knowledge from other individuals or from parents in the case of species with parental care. The age-structured bit string allows us to study how knowledge is accumulated during life and its influence over the genetic pool of a population after many generations. We use the Penna model to represent the genetic inheritance of each individual. In order to study how the accumulated knowledge influences the survival process, we include it to help individuals to avoid the various death situations. Modifications in the Verhulst factor do not show any special feature due to its random nature. However, by adding years to life as a function of the accumulated knowledge, we observe an improvement of the survival rates while the genetic fitness of the population becomes worse. In this latter case, knowledge becomes more important in the last years of life where individuals are threatened by diseases. Effects of offspring overprotection and differences between individual and social learning can also be observed. Sexual selection as a function of knowledge shows some effects when fidelity is imposed.

Interests in high-functioning autism are more intense, interfering, and idiosyncratic, but not more circumscribed, than those in neurotypical development

PubMed Central

Anthony, Laura Gutermuth; Kenworthy, Lauren; Yerys, Benjamin E.; Jankowski, Kathryn F.; James, Joette D.; Harms, Madeline B.; Martin, Alex; Wallace, Gregory L.

2015-01-01

Though circumscribed interests are pathognomonic with autism, how these interests differ from those expressed during neutotypical (NT) development remains unknown. Using a novel measure, the Interests Scale (IS), this study compares interests between 76 NT individuals and 109 individuals with high-functioning autism spectrum disorder (HF-ASD) matched group-wise on age, IQ and gender ratio. Participants and their parents/caregivers completed diagnostic measures (Autism Diagnostic Interview-Revised [ADI-R], Autism Diagnostic Observation Schedule [ADOS]; HF-ASD only), cognitive tests (Wechsler IQ Scales), and questionnaires (the Repetitive Behavior Scale-Revised [RBS-R], the Behavior Rating Inventory of Executive Function [BRIEF], and the Social Responsiveness Scale [SRS]), in addition to the IS. HF-ASD and NT individuals did not differ in number of interest areas, but the types of interests differed considerably. HF-ASD individuals had significantly more intense and interfering interests than NT individuals. Using only the intensity score, 77.5% of individuals were correctly classified (NT or HF-ASD) in a discriminant function analysis. Among individuals with HF-ASD, IS scores were significantly related to ADOS, BRIEF, RBS-R and SRS scores, but not to ADI-R scores, IQ, gender, age or psychotropic medication use. The type and intensity, but not the number, of interests distinguish high-functioning children with ASD from NT children. PMID:23880382

Preference assessments in the zoo: Keeper and staff predictions of enrichment preferences across species.

PubMed

Mehrkam, Lindsay R; Dorey, Nicole R

2015-01-01

Environmental enrichment is widely used in the management of zoo animals, and is an essential strategy for increasing the behavioral welfare of these populations. It may be difficult, however, to identify potentially effective enrichment strategies that are also cost-effective and readily available. An animal's preference for a potential enrichment item may be a reliable predictor of whether that individual will reliably interact with that item, and subsequently enable staff to evaluate the effects of that enrichment strategy. The aim of the present study was to assess the utility of preference assessments for identifying potential enrichment items across six different species--each representing a different taxonomic group. In addition, we evaluated the agreement between zoo personnel's predictions of animals' enrichment preferences and stimuli selected via a preference assessment. Five out of six species (nine out of 11 individuals) exhibited clear, systematic preferences for specific stimuli. Similarities in enrichment preferences were observed among all individuals of primates, whereas individuals within ungulate and avian species displayed individual differences in enrichment preferences. Overall, zoo personnel, regardless of experience level, were significantly more accurate at predicting least-preferred stimuli than most-preferred stimuli across species, and tended to make the same predictions for all individuals within a species. Preference assessments may therefore be a useful, efficient husbandry strategy for identifying viable enrichment items at both the individual and species levels. © 2015 Wiley Periodicals, Inc.

Estimating individual contribution from group-based structural correlation networks.

PubMed

Saggar, Manish; Hosseini, S M Hadi; Bruno, Jennifer L; Quintin, Eve-Marie; Raman, Mira M; Kesler, Shelli R; Reiss, Allan L

2015-10-15

Coordinated variations in brain morphology (e.g., cortical thickness) across individuals have been widely used to infer large-scale population brain networks. These structural correlation networks (SCNs) have been shown to reflect synchronized maturational changes in connected brain regions. Further, evidence suggests that SCNs, to some extent, reflect both anatomical and functional connectivity and hence provide a complementary measure of brain connectivity in addition to diffusion weighted networks and resting-state functional networks. Although widely used to study between-group differences in network properties, SCNs are inferred only at the group-level using brain morphology data from a set of participants, thereby not providing any knowledge regarding how the observed differences in SCNs are associated with individual behavioral, cognitive and disorder states. In the present study, we introduce two novel distance-based approaches to extract information regarding individual differences from the group-level SCNs. We applied the proposed approaches to a moderately large dataset (n=100) consisting of individuals with fragile X syndrome (FXS; n=50) and age-matched typically developing individuals (TD; n=50). We tested the stability of proposed approaches using permutation analysis. Lastly, to test the efficacy of our method, individual contributions extracted from the group-level SCNs were examined for associations with intelligence scores and genetic data. The extracted individual contributions were stable and were significantly related to both genetic and intelligence estimates, in both typically developing individuals and participants with FXS. We anticipate that the approaches developed in this work could be used as a putative biomarker for altered connectivity in individuals with neurodevelopmental disorders. Copyright © 2015 Elsevier Inc. All rights reserved.

Individual Differences in Second Language Sentence Processing

ERIC Educational Resources Information Center

Roberts, Leah

2012-01-01

As is the case in traditional second language (L2) acquisition research, a major question in the field of L2 real-time sentence processing is the extent to which L2 learners process the input like native speakers. Where differences are observed, the underlying causes could be the influence of the learner's first language and/or differences…

Sex, Intelligence and Educational Achievement in a National Cohort of over 175,000 11-Year-Old Schoolchildren in England

ERIC Educational Resources Information Center

Calvin, Catherine M.; Fernandes, Cres; Smith, Pauline; Visscher, Peter M.; Deary, Ian J.

2010-01-01

General cognitive ability ("g") does not explain sex differences in academic test performance by the end of compulsory education. Instead, individual differences in specific reasoning abilities, after removing the effects of "g," may contribute to the observed gender gaps. Associations between general or specific cognitive…

Individual Differences in the Multisensory Temporal Binding Window Predict Susceptibility to Audiovisual Illusions

ERIC Educational Resources Information Center

Stevenson, Ryan A.; Zemtsov, Raquel K.; Wallace, Mark T.

2012-01-01

Human multisensory systems are known to bind inputs from the different sensory modalities into a unified percept, a process that leads to measurable behavioral benefits. This integrative process can be observed through multisensory illusions, including the McGurk effect and the sound-induced flash illusion, both of which demonstrate the ability of…

Pragmatic Development as a Dynamic, Complex Process: General Patterns and Case Histories

ERIC Educational Resources Information Center

Taguchi, Naoko

2011-01-01

This longitudinal study asks 2 questions. The first one is: What patterns of pragmatic development can we observe among different pragmatic functions and attributes in a second language (L2)? The second question is: In what ways do individual differences and learning context affect the course of pragmatic development? Forty-eight Japanese college…

Effects of a Classroom Intervention with Spatial Play Materials on Children's Object and Viewer Transformation Abilities

ERIC Educational Resources Information Center

Vander Heyden, Karin M.; Huizinga, Mariette; Jolles, Jelle

2017-01-01

Children practice their spatial skills when playing with spatial toys, such as construction materials, board games, and puzzles. Sex and SES differences are observed in the engagement in such spatial play activities at home, which relate to individual differences in spatial performance. The current study investigated the effects of explicitly…

Nucleus accumbens response to gains in reputation for the self relative to gains for others predicts social media use

PubMed Central

Meshi, Dar; Morawetz, Carmen; Heekeren, Hauke R.

2013-01-01

Our reputation is important to us; we've experienced natural selection to care about our reputation. Recently, the neural processing of gains in reputation (positive social feedback concerning one's character) has been shown to occur in the human ventral striatum. It is still unclear, however, how individual differences in the processing of gains in reputation may lead to individual differences in real-world behavior. For example, in the real-world, one way that people currently maintain their reputation is by using social media websites, like Facebook. Furthermore, Facebook use consists of a social comparison component, where users observe others' behavior and can compare it to their own. Therefore, we hypothesized a relationship between the way the brain processes specifically self-relevant gains in reputation and one's degree of Facebook use. We recorded functional neuroimaging data while participants received gains in reputation, observed the gains in reputation of another person, or received monetary reward. We demonstrate that across participants, when responding to gains in reputation for the self, relative to observing gains for others, reward-related activity in the left nucleus accumbens predicts Facebook use. However, nucleus accumbens activity in response to monetary reward did not predict Facebook use. Finally, a control step-wise regression analysis showed that Facebook use primarily explains our results in the nucleus accumbens. Overall, our results demonstrate how individual sensitivity of the nucleus accumbens to the receipt of self-relevant social information leads to differences in real-world behavior. PMID:24009567

Insights from triangulation of two purchase choice elicitation methods to predict social decision making in healthcare.

PubMed

Whitty, Jennifer A; Rundle-Thiele, Sharyn R; Scuffham, Paul A

2012-03-01

Discrete choice experiments (DCEs) and the Juster scale are accepted methods for the prediction of individual purchase probabilities. Nevertheless, these methods have seldom been applied to a social decision-making context. To gain an overview of social decisions for a decision-making population through data triangulation, these two methods were used to understand purchase probability in a social decision-making context. We report an exploratory social decision-making study of pharmaceutical subsidy in Australia. A DCE and selected Juster scale profiles were presented to current and past members of the Australian Pharmaceutical Benefits Advisory Committee and its Economic Subcommittee. Across 66 observations derived from 11 respondents for 6 different pharmaceutical profiles, there was a small overall median difference of 0.024 in the predicted probability of public subsidy (p = 0.003), with the Juster scale predicting the higher likelihood. While consistency was observed at the extremes of the probability scale, the funding probability differed over the mid-range of profiles. There was larger variability in the DCE than Juster predictions within each individual respondent, suggesting the DCE is better able to discriminate between profiles. However, large variation was observed between individuals in the Juster scale but not DCE predictions. It is important to use multiple methods to obtain a complete picture of the probability of purchase or public subsidy in a social decision-making context until further research can elaborate on our findings. This exploratory analysis supports the suggestion that the mixed logit model, which was used for the DCE analysis, may fail to adequately account for preference heterogeneity in some contexts.

Proliferation-dependent positioning of individual centromeres in the interphase nucleus of human lymphoblastoid cell lines

PubMed Central

Ollion, Jean; Loll, François; Cochennec, Julien; Boudier, Thomas; Escudé, Christophe

2015-01-01

The cell nucleus is a highly organized structure and plays an important role in gene regulation. Understanding the mechanisms that sustain this organization is therefore essential for understanding genome function. Centromeric regions (CRs) of chromosomes have been known for years to adopt specific nuclear positioning patterns, but the significance of this observation is not yet completely understood. Here, using a combination of fluorescence in situ hybridization and immunochemistry on fixed human cells and high-throughput imaging, we directly and quantitatively investigated the nuclear positioning of specific human CRs. We observe differential attraction of individual CRs toward both the nuclear border and the nucleoli, the former being enhanced in nonproliferating cells and the latter being enhanced in proliferating cells. Similar positioning patterns are observed in two different lymphoblastoid cell lines. Moreover, the positioning of CRs differs from that of noncentromeric regions, and CRs display specific orientations within chromosome territories. These results suggest the existence of not-yet-characterized mechanisms that drive the nuclear positioning of CRs and therefore pave the way toward a better understanding of how CRs affect nuclear organization. PMID:25947134

Differences in the Fecal Concentrations and Genetic Diversities of Campylobacter jejuni Populations among Individual Cows in Two Dairy Herds

PubMed Central

Ross, Colleen M.; Pleydell, Eve J.; Muirhead, Richard W.

2012-01-01

Dairy cows have been identified as common carriers of Campylobacter jejuni, which causes many of the human gastroenteritis cases reported worldwide. To design on-farm management practices that control the human infection sourced from dairy cows, the first step is to acquire an understanding of the excretion patterns of the cow reservoir. We monitored the same 35 cows from two dairy farms for C. jejuni excretion fortnightly for up to 12 months. The objective was to examine the concentration of C. jejuni and assess the genetic relationship of the C. jejuni populations excreted by individual cows. Significant differences (P < 0.01) in C. jejuni fecal concentration were observed among the 35 cows, with median concentrations that varied by up to 3.6 log10 · g−1 feces. A total of 36 different genotypes were identified from the 514 positive samples by using enterobacterial repetitive intergenic consensus (ERIC)-PCR. Although 22 of these genotypes were excreted by more than one cow, the analysis of frequencies and distribution of the genotypes by model-based statistics revealed a high degree of individuality in the C. jejuni population in each cow. The observed variation in the frequency of excretion of a genotype among cows and the analysis by multilocus sequence typing (MLST) of these genotypes suggest that excretion of C. jejuni in high numbers is due to a successful adaptation of a particular genotype to a particular cow's gut environment, but that animal-related factors render some individual cows resistant to colonization by particular genotypes. The reasons for differences in C. jejuni colonization of animals warrant further investigation. PMID:22904055

Time-activity relationships to VOC personal exposure factors

NASA Astrophysics Data System (ADS)

Edwards, Rufus D.; Schweizer, Christian; Llacqua, Vito; Lai, Hak Kan; Jantunen, Matti; Bayer-Oglesby, Lucy; Künzli, Nino

Social and demographic factors have been found to play a significant role in differences between time-activity patterns of population subgroups. Since time-activity patterns largely influence personal exposure to compounds as individuals move across microenvironments, exposure subgroups within the population may be defined by factors that influence daily activity patterns. Socio-demographic and environmental factors that define time-activity subgroups also define quantifiable differences in VOC personal exposures to different sources and individual compounds in the Expolis study. Significant differences in exposures to traffic-related compounds ethylbenzene, m- and p-xylene and o-xylene were observed in relation to gender, number of children and living alone. Categorization of exposures further indicated time exposed to traffic at work and time in a car as important determinants. Increased exposures to decane, nonane and undecane were observed for males, housewives and self-employed. Categorization of exposures indicated exposure subgroups related to workshop use and living downtown. Higher exposures to 3-carene and α-pinene commonly found in household cleaning products and fragrances were associated with more children, while exposures to traffic compounds ethylbenzene, m- and p-xylene and o-xylene were reduced with more children. Considerable unexplained variation remained in categorization of exposures associated with home product use and fragrances, due to individual behavior and product choice. More targeted data collection methods in VOC exposure studies for these sources should be used. Living alone was associated with decreased exposures to 2-methyl-1-propanol and 1-butanol, and traffic-related compounds. Identification of these subgroups may help to reduce the large amount of unexplained variation in VOC exposure studies. Further they may help in assessing impacts of urban planning that result in changes in behavior of individuals, resulting in shifts in the patterns of exposure experienced by the population.

Autistic fluid intelligence: Increased reliance on visual functional connectivity with diminished modulation of coupling by task difficulty.

PubMed

Simard, Isabelle; Luck, David; Mottron, Laurent; Zeffiro, Thomas A; Soulières, Isabelle

2015-01-01

Different test types lead to different intelligence estimates in autism, as illustrated by the fact that autistic individuals obtain higher scores on the Raven's Progressive Matrices (RSPM) test than they do on the Wechsler IQ, in contrast to relatively similar performance on both tests in non-autistic individuals. However, the cerebral processes underlying these differences are not well understood. This study investigated whether activity in the fluid "reasoning" network, which includes frontal, parietal, temporal and occipital regions, is differently modulated by task complexity in autistic and non-autistic individuals during the RSPM. In this purpose, we used fMRI to study autistic and non-autistic participants solving the 60 RSPM problems focussing on regions and networks involved in reasoning complexity. As complexity increased, activity in the left superior occipital gyrus and the left middle occipital gyrus increased for autistic participants, whereas non-autistic participants showed increased activity in the left middle frontal gyrus and bilateral precuneus. Using psychophysiological interaction analyses (PPI), we then verified in which regions did functional connectivity increase as a function of reasoning complexity. PPI analyses revealed greater connectivity in autistic, compared to non-autistic participants, between the left inferior occipital gyrus and areas in the left superior frontal gyrus, right superior parietal lobe, right middle occipital gyrus and right inferior temporal gyrus. We also observed generally less modulation of the reasoning network as complexity increased in autistic participants. These results suggest that autistic individuals, when confronted with increasing task complexity, rely mainly on visuospatial processes when solving more complex matrices. In addition to the now well-established enhanced activity observed in visual areas in a range of tasks, these results suggest that the enhanced reliance on visual perception has a central role in autistic cognition.

Autistic fluid intelligence: Increased reliance on visual functional connectivity with diminished modulation of coupling by task difficulty

PubMed Central

Simard, Isabelle; Luck, David; Mottron, Laurent; Zeffiro, Thomas A.; Soulières, Isabelle

2015-01-01

Different test types lead to different intelligence estimates in autism, as illustrated by the fact that autistic individuals obtain higher scores on the Raven's Progressive Matrices (RSPM) test than they do on the Wechsler IQ, in contrast to relatively similar performance on both tests in non-autistic individuals. However, the cerebral processes underlying these differences are not well understood. This study investigated whether activity in the fluid “reasoning” network, which includes frontal, parietal, temporal and occipital regions, is differently modulated by task complexity in autistic and non-autistic individuals during the RSPM. In this purpose, we used fMRI to study autistic and non-autistic participants solving the 60 RSPM problems focussing on regions and networks involved in reasoning complexity. As complexity increased, activity in the left superior occipital gyrus and the left middle occipital gyrus increased for autistic participants, whereas non-autistic participants showed increased activity in the left middle frontal gyrus and bilateral precuneus. Using psychophysiological interaction analyses (PPI), we then verified in which regions did functional connectivity increase as a function of reasoning complexity. PPI analyses revealed greater connectivity in autistic, compared to non-autistic participants, between the left inferior occipital gyrus and areas in the left superior frontal gyrus, right superior parietal lobe, right middle occipital gyrus and right inferior temporal gyrus. We also observed generally less modulation of the reasoning network as complexity increased in autistic participants. These results suggest that autistic individuals, when confronted with increasing task complexity, rely mainly on visuospatial processes when solving more complex matrices. In addition to the now well-established enhanced activity observed in visual areas in a range of tasks, these results suggest that the enhanced reliance on visual perception has a central role in autistic cognition. PMID:26594629

An Investigation of Individual Variability in Brain Activity During Episodic Encoding and Retrieval

DTIC Science & Technology

2008-12-01

variability in mnemonic strategy use is, at least in part, related to the extensive variability observed in brain activity patterns. While a number of...1 AN INVESTIGATION OF INDIVIDUAL VARIABILITY IN BRAIN ACTIVITY DURING EPISODIC ENCODING AND RETRIEVAL C.L. Donovan*, and M.B. Miller Department of...strategy measures for predicting differences in brain activity patterns during a learning and memory task and to compare their predictive value to other

Cortical processing of speech in individuals with auditory neuropathy spectrum disorder.

PubMed

Apeksha, Kumari; Kumar, U Ajith

2018-06-01

Auditory neuropathy spectrum disorder (ANSD) is a condition where cochlear amplification function (involving outer hair cells) is normal but neural conduction in the auditory pathway is disordered. This study was done to investigate the cortical representation of speech in individuals with ANSD and to compare it with the individuals with normal hearing. Forty-five participants including 21 individuals with ANSD and 24 individuals with normal hearing were considered for the study. Individuals with ANSD had hearing thresholds ranging from normal hearing to moderate hearing loss. Auditory cortical evoked potentials-through odd ball paradigm-were recorded using 64 electrodes placed on the scalp for /ba/-/da/ stimulus. Onset cortical responses were also recorded in repetitive paradigm using /da/ stimuli. Sensitivity and reaction time required to identify the oddball stimuli were also obtained. Behavioural results indicated that individuals in ANSD group had significantly lower sensitivity and longer reaction times compared to individuals with normal hearing sensitivity. Reliable P300 could be elicited in both the groups. However, a significant difference in scalp topographies was observed between the two groups in both repetitive and oddball paradigms. Source localization using local auto regressive analyses revealed that activations were more diffuses in individuals with ANSD when compared to individuals with normal hearing sensitivity. Results indicated that the brain networks and regions activated in individuals with ANSD during detection and discrimination of speech sounds are different from normal hearing individuals. In general, normal hearing individuals showed more focused activations while in individuals with ANSD activations were diffused.

Mandatory pre-marital HIV testing in Nigeria: the public health and social implications.

PubMed

Uneke, C J; Alo, M; Ogbu, O

2007-01-01

The prevalence of HIV infection among individuals referred from faith-based organizations (FBOs) in south-eastern Nigeria for mandatory pre-marital HIV screening was determined. Of the total of 319 individuals (148 males, 171 females) screened, 25 (7.8%, 95%CI: 4.9-10.7%) were confirmed HIV-positive, comprising 13 (8.8%, 95%CI: 4.2-13.4%) males and 12 (7%, 95%CI: 3.2-10.8%) females. No significant difference was observed in the association between HIV infection and gender (chi2=0.58, df = 1, P < 0.05). The highest prevalence of HIV infection (8.9%) was recorded among individuals in the 21-30 years age category, while the least HIV infection prevalence (5.3%) was observed among persons above 40 years old. There was no significant difference in the association between HIV infection and age (chi2=0.68, df = 3, P < 0.05). Mandatory pre-marital HIV screening could generate social stigmatization and infringement of the fundamental human rights of infected individuals. Voluntary counselling and confidential HIV testing and especially pre- and post-test counselling as the basis of pre-marital HIV testing are more desirable. Guidelines for the management of test-positive individuals and non-concordant couples and the safeguarding of confidentiality should be developed. Training and capacity building for religious leaders, to appropriately manage social issues associated with HIV/AIDS as it affects their organizations, are recommended.

Modeling infection transmission in primate networks to predict centrality-based risk.

PubMed

Romano, Valéria; Duboscq, Julie; Sarabian, Cécile; Thomas, Elodie; Sueur, Cédric; MacIntosh, Andrew J J

2016-07-01

Social structure can theoretically regulate disease risk by mediating exposure to pathogens via social proximity and contact. Investigating the role of central individuals within a network may help predict infectious agent transmission as well as implement disease control strategies, but little is known about such dynamics in real primate networks. We combined social network analysis and a modeling approach to better understand transmission of a theoretical infectious agent in wild Japanese macaques, highly social animals which form extended but highly differentiated social networks. We collected focal data from adult females living on the islands of Koshima and Yakushima, Japan. Individual identities as well as grooming networks were included in a Markov graph-based simulation. In this model, the probability that an individual will transmit an infectious agent depends on the strength of its relationships with other group members. Similarly, its probability of being infected depends on its relationships with already infected group members. We correlated: (i) the percentage of subjects infected during a latency-constrained epidemic; (ii) the mean latency to complete transmission; (iii) the probability that an individual is infected first among all group members; and (iv) each individual's mean rank in the chain of transmission with different individual network centralities (eigenvector, strength, betweenness). Our results support the hypothesis that more central individuals transmit infections in a shorter amount of time and to more subjects but also become infected more quickly than less central individuals. However, we also observed that the spread of infectious agents on the Yakushima network did not always differ from expectations of spread on random networks. Generalizations about the importance of observed social networks in pathogen flow should thus be made with caution, since individual characteristics in some real world networks appear less relevant than they are in others in predicting disease spread. Am. J. Primatol. 78:767-779, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Antioxidant Activity of Individual Steryl Ferulates from Various Cereal Grain Sources.

PubMed

Zhu, Dan; Sánchez-Ferrer, Antoni; Nyström, Laura

2016-02-26

Steryl ferulates (SFs) are a subclass of bioactive lipids contributing to the health-promoting effects of whole grains. Most related studies focus on γ-oryzanol, a SF mixture from rice, since individual steryl ferulates are not commercially available. There is little evidence that individual SFs may vary in their bioactivity. The aim of this study was to evaluate the antioxidant activity of eight individual SFs by determining their radical scavenging capacity. Additional molecular properties of the individual SFs were determined by molecular simulation in order to identify correlations with their antioxidant activities. Our study demonstrates that individual SFs exhibit 1,1-diphenyl-2-picrylhydrazyl radical, hydroxyl radical, and superoxide anion radical scavenging abilities with subtle differences that were highly dependent on the kind of reaction taking place. The grouping of SFs by principle component analysis was mainly attributed to molecular properties, not antioxidant activities. Solvation energy was significantly correlated with some experimental observations. To our knowledge, this is the first study to evaluate the antioxidant activity of eight individual steryl ferulates from different sources. Results of this work will provide better insight into the antioxidant activity of SFs and the health benefits of whole grains.

Population genetic differentiation of height and body mass index across Europe

PubMed Central

Robinson, Matthew R.; Hemani, Gibran; Medina-Gomez, Carolina; Mezzavilla, Massimo; Esko, Tonu; Shakhbazov, Konstantin; Powell, Joseph E.; Vinkhuyzen, Anna; Berndt, Sonja I.; Gustafsson, Stefan; Justice, Anne E.; Kahali, Bratati; Locke, Adam E.; Pers, Tune H.; Vedantam, Sailaja; Wood, Andrew R.; van Rheenen, Wouter; Andreassen, Ole A.; Gasparini, Paolo; Metspalu, Andres; van den Berg, Leonard H.; Veldink, Jan H.; Rivadeneira, Fernando; Werge, Thomas M.; Abecasis, Goncalo R.; Boomsma, Dorret I.; Chasman, Daniel I.; de Geus, Eco J.C.; Frayling, Timothy M.; Hirschhorn, Joel N.; Hottenga, Jouke Jan; Ingelsson, Erik; Loos, Ruth J.F.; Magnusson, Patrik K. E.; Martin, Nicholas G.; Montgomery, Grant W.; North, Kari E.; Pedersen, Nancy L.; Spector, Timothy D.; Speliotes, Elizabeth K.; Goddard, Michael E.; Yang, Jian; Visscher, Peter M.

2016-01-01

Across-nation differences in the mean of complex traits such as obesity and stature are common1–8, but the reasons for these differences are not known. Here, we find evidence that many independent loci of small effect combine to create population genetic differences in height and body mass index (BMI) in a sample of 9,416 individuals across 14 European countries. Using discovery data on over 250,000 individuals and unbiased estimates of effect sizes from 17,500 sib pairs, we estimate that 24% (95% CI: 9%, 41%) and 8% (95% CI: 4%, 16%) of the captured additive genetic variance for height and BMI across Europe are attributed to among-population genetic differences. Population genetic divergence differed significantly from that expected under a null model (P <3.94e−08 for height and P<5.95e−04 for BMI), and we find an among-population genetic correlation for tall and slender nations (r = −0.80 (95% CI: −0.95, −0.60), contrasting no genetic correlation between height and BMI within populations (r = −0.016, 95% CI: −0.041, 0.001), consistent with selection on height genes that also act to reduce BMI. Observations of mean height across nations correlated with the predicted genetic means for height (r = 0.51, P<0.001), so that a proportion of observed differences in height within Europe reflect genetic factors. In contrast, observed mean BMI did not correlate with the genetic estimates (P<0.58), implying that genetic differentiation in BMI is masked by environmental differences across Europe. PMID:26366552

Juvenile social relationships reflect adult patterns of behavior in wild geladas.

PubMed

Barale, Caitlin L; Rubenstein, Daniel I; Beehner, Jacinta C

2015-10-01

Unlike many mammals, primates spend much of their lives as reproductively-immature juveniles. During the juvenile period, they develop social relationships and physical skills that both facilitate survival to adulthood and impact adult fitness. In this study, we use 2 years of observational data to examine the development of these skills across the juvenile period in a wild cercopithecine primate, the gelada (Theropithecus gelada). As adults, male and female geladas require different skills to be successful; we therefore expected sex differences in social behavior and partner choice during the juvenile period to already reflect these sex-specific trajectories. For example, males, who disperse at puberty and ultimately must challenge other adult males for access to mates, should invest in high-energy play-fighting with other males to develop fighting and rival assessment skills. In contrast, philopatric females, who remain with their close kin throughout their lives, should invest more in forming less-physical and more-social bonds with other females within their group. As predicted, sex differences that foreshadowed sex-specific adult roles were apparent in play rates, the average number of play partners per individual, grooming partner types and social partner preferences. Males played more and had more play partners than same-age females. Males also groomed more often with individuals from outside their natal group than females, although no sex difference was observed in either grooming rates or number of grooming partners per individual. Females stopped playing earlier than males, and instead invested in grooming relationships with close relatives. Additionally, we found that individual play and grooming rates were temporally consistent for both males and females (i.e., from one year to the next year), suggesting that individuals exhibit stable behavioral phenotypes. We conclude by discussing how early life in geladas may shape adult behavior and reproductive strategies. © 2015 Wiley Periodicals, Inc.

Congruent Strain Specific Intestinal Persistence of Lactobacillus plantarum in an Intestine-Mimicking In Vitro System and in Human Volunteers

PubMed Central

van Bokhorst-van de Veen, Hermien; van Swam, Iris; Wels, Michiel; Bron, Peter A.; Kleerebezem, Michiel

2012-01-01

Background An important trait of probiotics is their capability to reach their intestinal target sites alive to optimally exert their beneficial effects. Assessment of this trait in intestine-mimicking in vitro model systems has revealed differential survival of individual strains of a species. However, data on the in situ persistence characteristics of individual or mixtures of strains of the same species in the gastrointestinal tract of healthy human volunteers have not been reported to date. Methodology/Principal Findings The GI-tract survival of individual L. plantarum strains was determined using an intestine mimicking model system, revealing substantial inter-strain differences. The obtained data were correlated to genomic diversity of the strains using comparative genome hybridization (CGH) datasets, but this approach failed to discover specific genetic loci that explain the observed differences between the strains. Moreover, we developed a next-generation sequencing-based method that targets a variable intergenic region, and employed this method to assess the in vivo GI-tract persistence of different L. plantarum strains when administered in mixtures to healthy human volunteers. Remarkable consistency of the strain-specific persistence curves were observed between individual volunteers, which also correlated significantly with the GI-tract survival predicted on basis of the in vitro assay. Conclusion The survival of individual L. plantarum strains in the GI-tract could not be correlated to the absence or presence of specific genes compared to the reference strain L. plantarum WCFS1. Nevertheless, in vivo persistence analysis in the human GI-tract confirmed the strain-specific persistence, which appeared to be remarkably similar in different healthy volunteers. Moreover, the relative strain-specific persistence in vivo appeared to be accurately and significantly predicted by their relative survival in the intestine-mimicking in vitro assay, supporting the use of this assay for screening of strain-specific GI persistence. PMID:22970257

Estimating survival and breeding probability for pond-breeding amphibians: a modified robust design

USGS Publications Warehouse

Bailey, L.L.; Kendall, W.L.; Church, D.R.; Wilbur, H.M.

2004-01-01

Many studies of pond-breeding amphibians involve sampling individuals during migration to and from breeding habitats. Interpreting population processes and dynamics from these studies is difficult because (1) only a proportion of the population is observable each season, while an unknown proportion remains unobservable (e.g., non-breeding adults) and (2) not all observable animals are captured. Imperfect capture probability can be easily accommodated in capture?recapture models, but temporary transitions between observable and unobservable states, often referred to as temporary emigration, is known to cause problems in both open- and closed-population models. We develop a multistate mark?recapture (MSMR) model, using an open-robust design that permits one entry and one exit from the study area per season. Our method extends previous temporary emigration models (MSMR with an unobservable state) in two ways. First, we relax the assumption of demographic closure (no mortality) between consecutive (secondary) samples, allowing estimation of within-pond survival. Also, we add the flexibility to express survival probability of unobservable individuals (e.g., ?non-breeders?) as a function of the survival probability of observable animals while in the same, terrestrial habitat. This allows for potentially different annual survival probabilities for observable and unobservable animals. We apply our model to a relictual population of eastern tiger salamanders (Ambystoma tigrinum tigrinum). Despite small sample sizes, demographic parameters were estimated with reasonable precision. We tested several a priori biological hypotheses and found evidence for seasonal differences in pond survival. Our methods could be applied to a variety of pond-breeding species and other taxa where individuals are captured entering or exiting a common area (e.g., spawning or roosting area, hibernacula).

Living upside down: patterns of red coral settlement in a cave

PubMed Central

Rugiu, Luca; Cerrano, Carlo; Abbiati, Marco

2018-01-01

Background Larval settlement and intra-specific interactions during the recruitment phase are crucial in determining the distribution and density of sessile marine populations. Marine caves are confined and stable habitats. As such, they provide a natural laboratory to study the settlement and recruitment processes in sessile invertebrates, including the valuable Mediterranean red coral Corallium rubrum. In the present study, the spatial and temporal variability of red coral settlers in an underwater cave was investigated by demographic and genetic approaches. Methods Sixteen PVC tiles were positioned on the walls and ceiling of the Colombara Cave, Ligurian Sea, and recovered after twenty months. A total of 372 individuals of red coral belonging to two different reproductive events were recorded. Basal diameter, height, and number of polyps were measured, and seven microsatellites loci were used to evaluate the genetic relationships among individuals and the genetic structure. Results Significant differences in the colonization rate were observed both between the two temporal cohorts and between ceiling and walls. No genetic structuring was observed between cohorts. Overall, high levels of relatedness among individuals were found. Conclusion The results show that C. rubrumindividuals on tiles are highly related at very small spatial scales, suggesting that nearby recruits are likely to be sibs. Self-recruitment and the synchronous settlement of clouds of larvae could be possible explanations for the observed pattern. PMID:29844950

Intra- and inter-observer agreement when using a descriptive classification scale for clinical assessment of faecal consistency in growing pigs.

PubMed

Pedersen, Ken Steen; Toft, Nils

2011-03-01

The objective of the current study was to evaluate intra- and inter-observer agreement using a descriptive classification scale with four categories, descriptive text and pictures for assessment of consistency in faecal samples from pigs post weaning. The four consistency categories were score one=firm and shaped, score two=soft and shaped, score three=loose and score four=watery. Five observers from the same veterinary practice examined 100 faecal samples using the scale with four categories. Four of the observers examined the 100 faecal samples twice within the same day. Within observers the difference in proportions for the individual consistency categories between two examinations was on average 0.04 (range: 0-0.10). The mean intra-observer agreement was 0.82 (range: 0.72-0.91) with a mean kappa value of 0.76 (range: 0.61-0.88). For inter-observer agreement overall kappa was 0.64. For the 10 pair-wise comparisons the mean inter-observer agreement was 0.73 (range: 0.61-0.90) with a mean kappa value of 0.64 (range: 0.48-0.87). The difference in proportions for the individual consistency categories was on average 0.08 (range: 0-0.17). In conclusion, the agreement observed for the descriptive classification scale with four categories, descriptive text and pictures may be categorized as a substantial to almost perfect intra-observer agreement and a moderate to almost perfect inter-observer agreement. However, more objective measures than clinical scales may still be needed to improve intra- and inter-observer agreement in research studies. Copyright © 2010 Elsevier B.V. All rights reserved.

Is There Any Difference between the In Situ and Systemic IL-10 and IFN-γ Production when Clinical Forms of Cutaneous Sporotrichosis Are Compared?

PubMed

Morgado, Fernanda N; Schubach, Armando O; Pimentel, Maria Inês; Lyra, Marcelo R; Vasconcellos, Érica C F; Valete-Rosalino, Claudia M; Conceição-Silva, Fátima

2016-01-01

Fungus of the Sporothrix schenckii complex can produce skin lesions in humans, commonly lymphocutaneous (LC) and fixed (F) forms of sporotrichosis. Some authors have suggested that clinical forms are influenced by differences in virulence and genetic profile of isolates. But little is known about the role of immune response in determining the clinical outcome of sporotrichosis. To verify the profile of systemic and in situ IFN-γ and IL-10 expression in sporotrichosis patients, and consequently to detect any difference between the two compartments and/or clinical presentation, we quantified the number of IFN-γ and IL-10 producer peripheral blood mononuclear cells stimulated with S. schenckii antigen (Ss-Ag) by Elispot, and quantified cytokines expression by in situ immunohistochemistry in the same patient. Three groups were formed: 1- LC (n = 9); 2- F (n = 10); 3- healthy individuals (n = 14). All sporotrichosis patients produced high amounts of systemic IFN- γ when compared to uninfected individuals. No differences were observed between LC and F groups. Regarding in situ IL-10 expression, a difference between LC and F groups was observed: LC lesions presented higher amounts of IL-10 than F lesions differently from systemic IL-10 which showed similarities. Our data suggests that LC lesions present higher IL-10 expression which could be related to regulatory mechanisms for compensating the tissue injury, however favoring fungal persistence in the lesions. Surprisingly, there were no differences in systemic and in situ IFN- γ expression between CL and F patients, although it was significantly higher expressed in these patients than in healthy individuals.

Is There Any Difference between the In Situ and Systemic IL-10 and IFN-γ Production when Clinical Forms of Cutaneous Sporotrichosis Are Compared?

PubMed Central

Morgado, Fernanda N.; Schubach, Armando O.; Pimentel, Maria Inês; Lyra, Marcelo R.; Vasconcellos, Érica C. F.; Valete-Rosalino, Claudia M.; Conceição-Silva, Fátima

2016-01-01

Fungus of the Sporothrix schenckii complex can produce skin lesions in humans, commonly lymphocutaneous (LC) and fixed (F) forms of sporotrichosis. Some authors have suggested that clinical forms are influenced by differences in virulence and genetic profile of isolates. But little is known about the role of immune response in determining the clinical outcome of sporotrichosis. To verify the profile of systemic and in situ IFN-γ and IL-10 expression in sporotrichosis patients, and consequently to detect any difference between the two compartments and/or clinical presentation, we quantified the number of IFN-γ and IL-10 producer peripheral blood mononuclear cells stimulated with S. schenckii antigen (Ss-Ag) by Elispot, and quantified cytokines expression by in situ immunohistochemistry in the same patient. Three groups were formed: 1- LC (n = 9); 2- F (n = 10); 3- healthy individuals (n = 14). All sporotrichosis patients produced high amounts of systemic IFN- γ when compared to uninfected individuals. No differences were observed between LC and F groups. Regarding in situ IL-10 expression, a difference between LC and F groups was observed: LC lesions presented higher amounts of IL-10 than F lesions differently from systemic IL-10 which showed similarities. Our data suggests that LC lesions present higher IL-10 expression which could be related to regulatory mechanisms for compensating the tissue injury, however favoring fungal persistence in the lesions. Surprisingly, there were no differences in systemic and in situ IFN- γ expression between CL and F patients, although it was significantly higher expressed in these patients than in healthy individuals. PMID:27622513

Spontaneous facial expressions of emotion of congenitally and noncongenitally blind individuals.

PubMed

Matsumoto, David; Willingham, Bob

2009-01-01

The study of the spontaneous expressions of blind individuals offers a unique opportunity to understand basic processes concerning the emergence and source of facial expressions of emotion. In this study, the authors compared the expressions of congenitally and noncongenitally blind athletes in the 2004 Paralympic Games with each other and with those produced by sighted athletes in the 2004 Olympic Games. The authors also examined how expressions change from 1 context to another. There were no differences between congenitally blind, noncongenitally blind, and sighted athletes, either on the level of individual facial actions or in facial emotion configurations. Blind athletes did produce more overall facial activity, but these were isolated to head and eye movements. The blind athletes' expressions differentiated whether they had won or lost a medal match at 3 different points in time, and there were no cultural differences in expression. These findings provide compelling evidence that the production of spontaneous facial expressions of emotion is not dependent on observational learning but simultaneously demonstrates a learned component to the social management of expressions, even among blind individuals.

Ratings of perceived exertion by women with internal or external locus of control.

PubMed

Hassmén, P; Koivula, N

1996-10-01

Ratings of perceived exertion are frequently used to estimate the strain and effort experienced subjectively by individuals during various forms of physical activity. A number of factors, both physiological and psychological in origin, have been suggested to work as modifiers of the exertion perceived by the individual. It has been reported in nonsport-related research that individuals with an internal locus of control seem to pay more attention to relevant information and use the available information more adequately than individuals with an external locus of control. The reputed inferior information-processing abilities of externals compared with internals could possibly also influence the ratings of perceived exertion, with externals being less accurate in their ratings. Whether locus of control might be such a factor was investigated. Fifty women worked on an ergometer cycle at four different work loads. The results showed statistically significant differences in subjective ratings of perceived exertion between externals and internals, especially at heavier work loads. Such differences might be because of unequal information-processing abilities, as the observed discrepancies occurred at higher work intensities, when more cues are available for processing.

The Effect of Sexual Experience on the Social Representation of Sex in Portuguese Young Adults.

PubMed

Gomes, Alexandra; Nunes, Cristina

2014-04-26

This study aimed to observe the effect of sexual experience on the social representation of sex in Portuguese young adults. According to social representation theory, the central core of the social representation should be the same in all individuals that share a common social ground, however differences should be found in the peripheral system. It was used a free evocation task to assess the social representation of sex in Portuguese individuals aging between 18 and 25 years old. Nine hundred and sixty individuals were grouped by their sexual experience and condom use habits. A prototypical analysis was conducted to assess the structure of the social representation and statistical differences were analyzed using the qui-square independency test to search for an association between the structure and the group evoking it. The results supported the hypothesis of a common central core for all groups that shows a romanticized vision of sex. The differences found in the peripheral system suggest that sexual experience affects the representation of sex in a way that seems clearer to these individuals the necessity of protection when it comes to sex.

Individual Differences in Visual Word Recognition: Insights from the English Lexicon Project

PubMed Central

Yap, Melvin J.; Balota, David A.; Sibley, Daragh E.; Ratcliff, Roger

2011-01-01

Empirical work and models of visual word recognition have traditionally focused on group-level performance. Despite the emphasis on the prototypical reader, there is clear evidence that variation in reading skill modulates word recognition performance. In the present study, we examined differences between individuals who contributed to the English Lexicon Project (http://elexicon.wustl.edu), an online behavioral database containing nearly four million word recognition (speeded pronunciation and lexical decision) trials from over 1,200 participants. We observed considerable within- and between-session reliability across distinct sets of items, in terms of overall mean response time (RT), RT distributional characteristics, diffusion model parameters (Ratcliff, Gomez, & McKoon, 2004), and sensitivity to underlying lexical dimensions. This indicates reliably detectable individual differences in word recognition performance. In addition, higher vocabulary knowledge was associated with faster, more accurate word recognition performance, attenuated sensitivity to stimuli characteristics, and more efficient accumulation of information. Finally, in contrast to suggestions in the literature, we did not find evidence that individuals were trading-off in their utilization of lexical and nonlexical information. PMID:21728459

An Analysis of Individual Differences in Recognizing Monosyllabic Words Under the Speech Intelligibility Index Framework

PubMed Central

Shen, Yi; Kern, Allison B.

2018-01-01

Individual differences in the recognition of monosyllabic words, either in isolation (NU6 test) or in sentence context (SPIN test), were investigated under the theoretical framework of the speech intelligibility index (SII). An adaptive psychophysical procedure, namely the quick-band-importance-function procedure, was developed to enable the fitting of the SII model to individual listeners. Using this procedure, the band importance function (i.e., the relative weights of speech information across the spectrum) and the link function relating the SII to recognition scores can be simultaneously estimated while requiring only 200 to 300 trials of testing. Octave-frequency band importance functions and link functions were estimated separately for NU6 and SPIN materials from 30 normal-hearing listeners who were naïve to speech recognition experiments. For each type of speech material, considerable individual differences in the spectral weights were observed in some but not all frequency regions. At frequencies where the greatest intersubject variability was found, the spectral weights were correlated between the two speech materials, suggesting that the variability in spectral weights reflected listener-originated factors. PMID:29532711

Age and CD161 Expression Contribute to Inter-Individual Variation in Interleukin-23 Response in CD8+ Memory Human T Cells

PubMed Central

Abraham, Clara; Cho, Judy H.

2013-01-01

The interleukin-23 (IL-23) pathway plays a critical role in the pathogenesis of multiple chronic inflammatory disorders, however, inter-individual variability in IL-23-induced signal transduction in circulating human lymphocytes has not been well-defined. In this study, we observed marked, reproducible inter-individual differences in IL-23 responsiveness (measured by STAT3 phosphorylation) in peripheral blood CD8+CD45RO+ memory T and CD3+CD56+ NKT cells. Age, but not gender, was a significant (Pearson’s correlation coefficient, r = −0.37, p = 0.001) source of variability observed in CD8+CD45RO+ memory T cells, with IL-23 responsiveness gradually decreasing with increasing age. Relative to cells from individuals demonstrating low responsiveness to IL-23 stimulation, CD8+CD45RO+ memory T cells from individuals demonstrating high responsiveness to IL-23 stimulation showed increased gene expression for IL-23 receptor (IL-23R), RORC (RORγt) and CD161 (KLRB1), whereas RORA (RORα) and STAT3 expression were equivalent. Similar to CD4+ memory T cells, IL-23 responsiveness is confined to the CD161+ subset in CD8+CD45RO+ memory T cells, suggesting a similar CD161+ precursor as has been reported for CD4+ Th17 cells. We observed a very strong positive correlation between IL-23 responsiveness and the fraction of CD161+, CD8+CD45RO+ memory T cells (r = 0.80, p<0.001). Moreover, the fraction of CD161+, CD8+CD45RO+ memory T cells gradually decreases with aging (r = −0.34, p = 0.05). Our data define the inter-individual differences in IL-23 responsiveness in peripheral blood lymphocytes from the general population. Variable expression of CD161, IL-23R and RORC affects IL-23 responsiveness and contributes to the inter-individual susceptibility to IL-23-mediated defenses and inflammatory processes. PMID:23469228

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

PubMed Central

Cuturi, Luigi F.; Gori, Monica

2017-01-01

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

Impact of Exercise Counseling on Physical Function in Chronic Kidney Disease: An Observational Study.

PubMed

Bohm, Clara J; Storsley, Leroy J; Hiebert, Brett M; Nelko, Serena; Tangri, Navdeep; Cheskin, Lawrence J; McAdams-DeMarco, Mara A; Rigatto, Claudio

2018-01-01

Individuals with chronic kidney disease (CKD) have low levels of physical activity and physical function. Although guidelines endorse exercise counseling for individuals with CKD, it is not yet part of routine care. We investigated the effect of attending a real-life exercise counseling clinic (ECC) on physical function in individuals with CKD. Retrospective analysis of prospectively collected observational data with quasi-experimental design. Patients with all stages of CKD registered in a large provincial renal program were eligible. The exposed cohort who attended the ECC between January 1, 2011, and March 15, 2014, included 214 individuals. The control cohort included 292 individuals enrolled in an observational study investigating longitudinal change in frailty during the same time period. Attendance at an ECC. Change in physical function as measured by Short Physical Performance Battery (SPPB) score, physical activity level (Human Activity Profile [HAP]/Physical Activity Scale for the Elderly [PASE]), and health-related quality of life (HRQOL; EQ5D/VAS) over 1 year. Eighty-seven individuals in the ECC cohort and 125 participants in the control cohort completed 1-year follow-up. Baseline median SPPB score was 10 (interquartile range [IQR]: 9-12) and 9 (IQR: 7-11) in the ECC and control cohorts, respectively ( P < .01). At 1 year, SPPB scores were 10 (IQR: 8-12) and 9 (IQR: 6-11) in the ECC and control cohorts, respectively ( P = .04). Mean change in SPPB over 1 year was not significantly different between groups: -0.33 (95% confidence interval [CI]: -0.81 to 0.15) in ECC and -0.22 (95% CI: -0.61 to 0.17) in control ( P = .72). There was no significant difference in the proportion of individuals in each cohort with an increase/decrease in SPPB score over time. There was no significant change in physical activity or HRQOL over time between groups. Quasi-experimental design, low rate of follow-up attendance. In this pragmatic study, exercise counseling had no significant effect on change in SPPB score, suggesting that a single exercise counseling session alone is inadequate to improve physical function in CKD.

Using data mining techniques to characterize participation in observational studies.

PubMed

Linden, Ariel; Yarnold, Paul R

2016-12-01

Data mining techniques are gaining in popularity among health researchers for an array of purposes, such as improving diagnostic accuracy, identifying high-risk patients and extracting concepts from unstructured data. In this paper, we describe how these techniques can be applied to another area in the health research domain: identifying characteristics of individuals who do and do not choose to participate in observational studies. In contrast to randomized studies where individuals have no control over their treatment assignment, participants in observational studies self-select into the treatment arm and therefore have the potential to differ in their characteristics from those who elect not to participate. These differences may explain part, or all, of the difference in the observed outcome, making it crucial to assess whether there is differential participation based on observed characteristics. As compared to traditional approaches to this assessment, data mining offers a more precise understanding of these differences. To describe and illustrate the application of data mining in this domain, we use data from a primary care-based medical home pilot programme and compare the performance of commonly used classification approaches - logistic regression, support vector machines, random forests and classification tree analysis (CTA) - in correctly classifying participants and non-participants. We find that CTA is substantially more accurate than the other models. Moreover, unlike the other models, CTA offers transparency in its computational approach, ease of interpretation via the decision rules produced and provides statistical results familiar to health researchers. Beyond their application to research, data mining techniques could help administrators to identify new candidates for participation who may most benefit from the intervention. © 2016 John Wiley & Sons, Ltd.

Individual Differences in Dynamic Functional Brain Connectivity across the Human Lifespan

PubMed Central

Davison, Elizabeth N.; Turner, Benjamin O.; Miller, Michael B.; Carlson, Jean M.

2016-01-01

Individual differences in brain functional networks may be related to complex personal identifiers, including health, age, and ability. Dynamic network theory has been used to identify properties of dynamic brain function from fMRI data, but the majority of analyses and findings remain at the level of the group. Here, we apply hypergraph analysis, a method from dynamic network theory, to quantify individual differences in brain functional dynamics. Using a summary metric derived from the hypergraph formalism—hypergraph cardinality—we investigate individual variations in two separate, complementary data sets. The first data set (“multi-task”) consists of 77 individuals engaging in four consecutive cognitive tasks. We observe that hypergraph cardinality exhibits variation across individuals while remaining consistent within individuals between tasks; moreover, the analysis of one of the memory tasks revealed a marginally significant correspondence between hypergraph cardinality and age. This finding motivated a similar analysis of the second data set (“age-memory”), in which 95 individuals, aged 18–75, performed a memory task with a similar structure to the multi-task memory task. With the increased age range in the age-memory data set, the correlation between hypergraph cardinality and age correspondence becomes significant. We discuss these results in the context of the well-known finding linking age with network structure, and suggest that hypergraph analysis should serve as a useful tool in furthering our understanding of the dynamic network structure of the brain. PMID:27880785

Predicting Smartphone Operating System from Personality and Individual Differences.

PubMed

Shaw, Heather; Ellis, David A; Kendrick, Libby-Rae; Ziegler, Fenja; Wiseman, Richard

2016-12-01

Android and iPhone devices account for over 90 percent of all smartphones sold worldwide. Despite being very similar in functionality, current discourse and marketing campaigns suggest that key individual differences exist between users of these two devices; however, this has never been investigated empirically. This is surprising, as smartphones continue to gain momentum across a variety of research disciplines. In this article, we consider if individual differences exist between these two distinct groups. In comparison to Android users, we found that iPhone owners are more likely to be female, younger, and increasingly concerned about their smartphone being viewed as a status object. Key differences in personality were also observed with iPhone users displaying lower levels of Honesty-Humility and higher levels of emotionality. Following this analysis, we were also able to build and test a model that predicted smartphone ownership at above chance level based on these individual differences. In line with extended self-theory, the type of smartphone owned provides some valuable information about its owner. These findings have implications for the increasing use of smartphones within research particularly for those working within Computational Social Science and PsychoInformatics, where data are typically collected from devices and applications running a single smartphone operating system.

The neural determinants of age-related changes in fluid intelligence: a pre-registered, longitudinal analysis in UK Biobank

PubMed Central

Kievit, Rogier A.; Fuhrmann, Delia; Henson, Richard N. A.

2018-01-01

Background: Fluid intelligence declines with advancing age, starting in early adulthood. Within-subject declines in fluid intelligence are highly correlated with contemporaneous declines in the ability to live and function independently. To support healthy aging, the mechanisms underlying these declines need to be better understood. Methods: In this pre-registered analysis, we applied latent growth curve modelling to investigate the neural determinants of longitudinal changes in fluid intelligence across three time points in 185,317 individuals (N=9,719 two waves, N=870 three waves) from the UK Biobank (age range: 39-73 years). Results: We found a weak but significant effect of cross-sectional age on the mean fluid intelligence score, such that older individuals scored slightly lower. However, the mean longitudinal slope was positive, rather than negative, suggesting improvement across testing occasions. Despite the considerable sample size, the slope variance was non-significant, suggesting no reliable individual differences in change over time. This null-result is likely due to the nature of the cognitive test used. In a subset of individuals, we found that white matter microstructure (N=8839, as indexed by fractional anisotropy) and grey-matter volume (N=9931) in pre-defined regions-of-interest accounted for complementary and unique variance in mean fluid intelligence scores. The strongest effects were such that higher grey matter volume in the frontal pole and greater white matter microstructure in the posterior thalamic radiations were associated with higher fluid intelligence scores. Conclusions: In a large preregistered analysis, we demonstrate a weak but significant negative association between age and fluid intelligence. However, we did not observe plausible longitudinal patterns, instead observing a weak increase across testing occasions, and no significant individual differences in rates of change, likely due to the suboptimal task design. Finally, we find support for our preregistered expectation that white- and grey matter make separate contributions to individual differences in fluid intelligence beyond age. PMID:29707655

Gait and functionality of individuals with visual impairment who participate in sports.

PubMed

da Silva, Edson Soares; Fischer, Gabriela; da Rosa, Rodrigo Gomes; Schons, Pedro; Teixeira, Luísa Beatriz Trevisan; Hoogkamer, Wouter; Peyré-Tartaruga, Leonardo Alexandre

2018-05-01

Individuals with visual impairment (VI) have often been observed to walk slower than individuals with unimpaired vision. These observations might be confounded by typical low levels of physical activity and greater sedentary behavior in individuals with VI than the overall population. Here, we compared gait and balance measures between individuals with VI who participate in disability sports, and activity level matched sighted individuals. We assessed static balance, anthropometry, self-selected walking speed, locomotion rehabilitation index, and lower limb muscular endurance; and applied physical activity level and fear of falling questionnaires. Individuals with VI who participate in disability sports, self-selected a similar walking speed (1.29 ± 0.26 m/s) as active sighted individuals (1.39 ± 0.21 m/s). Locomotor rehabilitation index and muscular endurance of lower limbs were also similar between groups. Individuals with VI presented lower static balance (42.0 ± 17.0s) than the sighted control group (45.0 ± 0s) when the controls were tested with their eyes open. However, no difference was found when the controls were tested with their eyes closed (30.3 ± 17.0s). Furthermore, individuals with VI showed a greater fear of falling. In conclusion, individuals with VI who participate in disability sports, as goalball and football, walk with similar self-selected walking speeds as active sighted individuals, but have slightly worse static balance and fear of falling. Copyright © 2018 Elsevier B.V. All rights reserved.

Ascertainment Bias Causes False Signal of Anticipation in Genetic Prion Disease

PubMed Central

Minikel, Eric Vallabh; Zerr, Inga; Collins, Steven J.; Ponto, Claudia; Boyd, Alison; Klug, Genevieve; Karch, André; Kenny, Joanna; Collinge, John; Takada, Leonel T.; Forner, Sven; Fong, Jamie C.; Mead, Simon; Geschwind, Michael D.

2014-01-01

Anticipation is the phenomenon whereby age of onset in genetic disease decreases in successive generations. Three independent reports have claimed anticipation in Creutzfeldt-Jakob disease (CJD) caused by the c.598G>A mutation in PRNP encoding a p.Glu200Lys (E200K) substitution in the prion protein. If confirmed, this finding would carry clear implications for genetic counseling. We analyzed pedigrees with this mutation from four prion centers worldwide (n = 217 individuals with the mutation) to analyze age of onset and death in affected and censored individuals. We show through simulation that selective ascertainment of individuals whose onset falls within the historical window since the mutation’s 1989 discovery is sufficient to create robust false signals both of anticipation and of heritability of age of onset. In our data set, the number of years of anticipation observed depends upon how strictly the data are limited by the ascertainment window. Among individuals whose disease was directly observed at a study center, a 28-year difference between parent and child age of onset is observed (p = 0.002), but including individuals ascertained retrospectively through family history reduces this figure to 7 years (p = 0.005). Applying survival analysis to the most thoroughly ascertained subset of data eliminates the signal of anticipation. Moreover, even non-CJD deaths exhibit 16 years anticipation (p = 0.002), indicating that ascertainment bias can entirely explain observed anticipation. We suggest that reports of anticipation in genetic prion disease are driven entirely by ascertainment bias. Guidelines for future studies claiming statistical evidence for anticipation are suggested. PMID:25279981

Unbroken mirror neurons in autism spectrum disorders.

PubMed

Fan, Yang-Teng; Decety, Jean; Yang, Chia-Yen; Liu, Ji-Lin; Cheng, Yawei

2010-09-01

The 'broken mirror' theory of autism, which proposes that a dysfunction of the human mirror neuron system (MNS) is responsible for the core social and cognitive deficits in individuals with autism spectrum disorders (ASD), has received considerable attention despite weak empirical evidence. In this electroencephalographic study, we examined mu suppression, as an indicator of sensorimotor resonance, concurrent with oculomotor performance while individuals (n = 20) with ASD and control participants (n = 20) either executed hand actions or observed hand actions or a moving dot. No difference in visual attention between groups was found as indicated by fixation duration and normalized fixation number on the presented stimuli. The mu suppression over the sensorimotor cortex was significantly affected by experimental conditions, but not by group membership, nor by the interaction between groups and conditions. Individuals with ASD, similar to the controls, exhibited stronger mu suppression when watching hand actions relative to a moving dot. Notably, participants with ASD failed to imitate the observed actions while their mu suppression indicating the MNS activity was intact. In addition, the mu suppression during the observation of hand actions was positively associated with the communication competence of individuals with ASD. Our study clearly challenges the broken mirror theory of autism. The functioning of the mirror neuron system might be preserved in individuals with ASD to a certain degree. Less mu suppression to action observation coupled with more communicational severity can reflect the symptom heterogeneity of ASD. Additional research needs to be done, and more caution should be used when reaching out to the media.

Robust patterning of gene expression based on internal coordinate system of cells.

PubMed

Ogawa, Ken-ichiro; Miyake, Yoshihiro

2015-06-01

Cell-to-cell communication in multicellular organisms is established through the transmission of various kinds of chemical substances such as proteins. It is well known that gene expression triggered by a chemical substance in individuals has stable spatial patterns despite the individual differences in concentration patterns of the chemical substance. This fact reveals an important property of multicellular organisms called "robustness", which allows the organisms to generate their forms while maintaining proportion. Robustness has been conventionally accounted for by the stability of solutions of dynamical equations that represent a specific interaction network of chemical substances. However, any biological system is composed of autonomous elements. In general, an autonomous element does not merely accept information on the chemical substance from the environment; instead, it accepts the information based on its own criteria for reaction. Therefore, this phenomenon needs to be considered from the viewpoint of cells. Such a viewpoint is expected to allow the consideration of the autonomy of cells in multicellular organisms. This study aims to explain theoretically the robust patterning of gene expression from the viewpoint of cells. For this purpose, we introduced a new operator for transforming a state variable of a chemical substance from an external coordinate system to an internal coordinate system of each cell, which describes the observation of the chemical substance by cells. We then applied this operator to the simplest reaction-diffusion model of the chemical substance to investigate observation effects by cells. Our mathematical analysis of this extended model indicates that the robust patterning of gene expression against individual differences in concentration pattern of the chemical substance can be explained from the viewpoint of cells if there is a regulation field that compensates for the difference between cells seen in the observation results. This result provides a new insight into the investigation of the mechanism of robust patterning in biological systems composed of individual elements. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Assessment of Unconstrained Cerebrovascular Reactivity Marker for Large Age-Range fMRI Studies

PubMed Central

Kannurpatti, Sridhar S.; Motes, Michael A.; Biswal, Bharat B.; Rypma, Bart

2014-01-01

Breath hold (BH), a commonly used task to measure cerebrovascular reactivity (CVR) in fMRI studies varies in outcome among individuals due to subject-physiology and/or BH-inspiration/expiration differences (i.e., performance). In prior age-related fMRI studies, smaller task-related BOLD response variability is observed among younger than older individuals. Also, a linear CVR versus task relationship exists in younger individuals which maybe useful to test the accuracy of CVR responses in older groups. Hence we hypothesized that subject-related physiological and/or BH differences, if present, may compromise CVR versus task linearity in older individuals. To test the hypothesis, empirical BH versus task relationships from motor and cognitive areas were obtained in younger (mean age = 26 years) and older (mean age = 58 years) human subjects. BH versus task linearity was observed only in the younger group, confirming our hypothesis. Further analysis indicated BH responses and its variability to be similar in both younger and older groups, suggesting that BH may not accurately represent CVR in a large age range. Using the resting state fluctuation of amplitude (RSFA) as an unconstrained alternative to BH, subject-wise correspondence between BH and RSFA was tested. Correlation between BH versus RSFA was significant within the motor but was not significant in the cognitive areas in the younger and was completely disrupted in both areas in the older subjects indicating that BH responses are constrained by subject-related physiology and/or performance-related differences. Contrasting BH to task, RSFA-task relationships were independent of age accompanied by age-related increases in CVR variability as measured by RSFA, not observed with BH. Together the results obtained indicate that RSFA accurately represents CVR in any age range avoiding multiple and yet unknown physiologic and task-related pitfalls of BH. PMID:24551151

Physiological and psychological individual differences influence resting brain function measured by ASL perfusion.

PubMed

Kano, M; Coen, S J; Farmer, A D; Aziz, Q; Williams, S C R; Alsop, D C; Fukudo, S; O'Gorman, R L

2014-09-01

Effects of physiological and/or psychological inter-individual differences on the resting brain state have not been fully established. The present study investigated the effects of individual differences in basal autonomic tone and positive and negative personality dimensions on resting brain activity. Whole-brain resting cerebral perfusion images were acquired from 32 healthy subjects (16 males) using arterial spin labeling perfusion MRI. Neuroticism and extraversion were assessed with the Eysenck Personality Questionnaire-Revised. Resting autonomic activity was assessed using a validated measure of baseline cardiac vagal tone (CVT) in each individual. Potential associations between the perfusion data and individual CVT (27 subjects) and personality score (28 subjects) were tested at the level of voxel clusters by fitting a multiple regression model at each intracerebral voxel. Greater baseline perfusion in the dorsal anterior cingulate cortex (ACC) and cerebellum was associated with lower CVT. At a corrected significance threshold of p < 0.01, strong positive correlations were observed between extraversion and resting brain perfusion in the right caudate, brain stem, and cingulate gyrus. Significant negative correlations between neuroticism and regional cerebral perfusion were identified in the left amygdala, bilateral insula, ACC, and orbitofrontal cortex. These results suggest that individual autonomic tone and psychological variability influence resting brain activity in brain regions, previously shown to be associated with autonomic arousal (dorsal ACC) and personality traits (amygdala, caudate, etc.) during active task processing. The resting brain state may therefore need to be taken into account when interpreting the neurobiology of individual differences in structural and functional brain activity.

Crotalus aquilus in the Mexican state of Mexico consumes a diverse summer diet

USGS Publications Warehouse

Mociño-deloya, E.; Setser, K.; Peurach, S.C.; Meik, J.M.

2008-01-01

We report observations of the summer diet of Crotalus aquilus (Queretaro dusky rattlesnake) from an agricultural region near San Pedro de los Metates, municipality of Acambay, state of Mexico, Mexico. We recovered the remains of 12 individual prey items from 11 different snakes. Eleven of 38 (29%) snakes observed contained prey remains, including 6 mammals, 3 lizards, and 3 snakes. These observations suggest that C. aquilus consumes a diverse diet and that they may be more ophiophagous than many other rattlesnakes.

Warning color changes in response to food deprivation in the pipevine swallowtail butterfly, Battus philenor.

PubMed

Pegram, Kimberly V; Nahm, Alexandra C; Rutowski, Ronald L

2013-01-01

Predation on distasteful animals should favor warning coloration that is relatively conspicuous and phenotypically invariable. However, even among similarly colored individuals there can be variation in their warning signals. In butterflies, individual differences in larval feeding history could cause this variation. The warning signal of the pipevine swallowtail butterfly, Battus philenor L. (Lepidoptera: Papilionidae) consists of both a blue iridescent patch and pigmentbased orange spots on the ventral hindwing. B. philenor males also display a dorsal surface iridescent patch that functions as a sexual indicator signal. A previous study of iridescence in B. philenor found that the iridescent blue on both the dorsal and ventral hind wings is variable and significantly different between lab-reared and field-caught individuals. These differences could be the result of larval food deprivation in the field. Through experimental manipulation of larval diet, larval food deprivation was evaluated as a potential cause of the differences observed between lab and field individuals, and if food deprivation is a source of inter-individual variation in warning signals. B. philenor larvae were food restricted starting at two points in the last larval instar, and one group was fed through pupation. Adult coloration was then compared. Food deprivation led to poorer adult condition, as indicated by lower adult body mass, forewing length, and fat content of stressed individuals. As the level of food deprivation increased, the hue of the iridescent patches on both the dorsal and ventral hind wing shifted to shorter wavelengths, and the chroma of the orange spots decreased. The shifts in iridescent color did not match the differences previously found between lab and field individuals. However, the treatment differences indicate that food deprivation may be a significant source of warning color variation. The differences between the treatment groups are likely detectable by predators, but the effect of the variation on signal effectiveness and function remains to be empirically explored.

A Campus-Wide Investigation of Clicker Implementation: The Status of Peer Discussion in STEM Classes

PubMed Central

Lewin, Justin D.; Vinson, Erin L.; Stetzer, MacKenzie R.; Smith, Michelle K.

2016-01-01

At the University of Maine, middle and high school teachers observed more than 250 university science, technology, engineering, and mathematics classes and collected information on the nature of instruction, including how clickers were being used. Comparisons of classes taught with (n = 80) and without (n = 184) clickers show that, while instructional behaviors differ, the use of clickers alone does not significantly impact the time instructors spend lecturing. One possible explanation stems from the observation of three distinct modes of clicker use: peer discussion, in which students had the opportunity to talk with one another during clicker questions; individual thinking, in which no peer discussion was observed; and alternative collaboration, in which students had time for discussion, but it was not paired with clicker questions. Investigation of these modes revealed differences in the range of behaviors, the amount of time instructors lecture, and how challenging the clicker questions were to answer. Because instructors can vary their instructional style from one clicker question to the next, we also explored differences in how individual instructors incorporated peer discussion during clicker questions. These findings provide new insights into the range of clicker implementation at a campus-wide level and how such findings can be used to inform targeted professional development for faculty. PMID:26931397

Why children differ in motivation to learn: Insights from over 13,000 twins from 6 countries.

PubMed

Kovas, Yulia; Garon-Carrier, Gabrielle; Boivin, Michel; Petrill, Stephen A; Plomin, Robert; Malykh, Sergey B; Spinath, Frank; Murayama, Kou; Ando, Juko; Bogdanova, Olga Y; Brendgen, Mara; Dionne, Ginette; Forget-Dubois, Nadine; Galajinsky, Eduard V; Gottschling, Juliana; Guay, Frédéric; Lemelin, Jean-Pascal; Logan, Jessica A R; Yamagata, Shinji; Shikishima, Chizuru; Spinath, Birgit; Thompson, Lee A; Tikhomirova, Tatiana N; Tosto, Maria G; Tremblay, Richard; Vitaro, Frank

2015-07-01

Little is known about why people differ in their levels of academic motivation. This study explored the etiology of individual differences in enjoyment and self-perceived ability for several school subjects in nearly 13,000 twins aged 9-16 from 6 countries. The results showed a striking consistency across ages, school subjects, and cultures. Contrary to common belief, enjoyment of learning and children's perceptions of their competence were no less heritable than cognitive ability. Genetic factors explained approximately 40% of the variance and all of the observed twins' similarity in academic motivation. Shared environmental factors, such as home or classroom, did not contribute to the twin's similarity in academic motivation. Environmental influences stemmed entirely from individual specific experiences.

The Chandra Source Catalog 2.0: Combining Data for Processing (or How I learned 17 different words for "group")

NASA Astrophysics Data System (ADS)

Hain, Roger; Allen, Christopher E.; Anderson, Craig S.; Budynkiewicz, Jamie A.; Burke, Douglas; Chen, Judy C.; Civano, Francesca Maria; D'Abrusco, Raffaele; Doe, Stephen M.; Evans, Ian N.; Evans, Janet D.; Fabbiano, Giuseppina; Gibbs, Danny G., II; Glotfelty, Kenny J.; Graessle, Dale E.; Grier, John D.; Hall, Diane M.; Harbo, Peter N.; Houck, John C.; Lauer, Jennifer L.; Laurino, Omar; Lee, Nicholas P.; Martínez-Galarza, Juan Rafael; McCollough, Michael L.; McDowell, Jonathan C.; Miller, Joseph; McLaughlin, Warren; Morgan, Douglas L.; Mossman, Amy E.; Nguyen, Dan T.; Nichols, Joy S.; Nowak, Michael A.; Paxson, Charles; Plummer, David A.; Primini, Francis Anthony; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Tibbetts, Michael; Van Stone, David W.; Zografou, Panagoula

2018-01-01

The Second Chandra Source Catalog (CSC2.0) combines data at multiple stages to improve detection efficiency, enhance source region identification, and match observations of the same celestial source taken with significantly different point spread functions on Chandra's detectors. The need to group data for different reasons at different times in processing results in a hierarchy of groups to which individual sources belong. Source data are initially identified as belonging to each Chandra observation ID and number (an "obsid"). Data from each obsid whose pointings are within sixty arcseconds of each other are reprojected to the same aspect reference coordinates and grouped into stacks. Detection is performed on all data in the same stack, and individual sources are identified. Finer source position and region data are determined by further processing sources whose photons may be commingled together, grouping such sources into bundles. Individual stacks which overlap to any extent are grouped into ensembles, and all stacks in the same ensemble are later processed together to identify master sources and determine their properties.We discuss the basis for the various methods of combining data for processing and precisely define how the groups are determined. We also investigate some of the issues related to grouping data and discuss what options exist and how groups have evolved from prior releases.This work has been supported by NASA under contract NAS 8-03060 to the Smithsonian Astrophysical Observatory for operation of the Chandra X-ray Center.

Drinking motives as mediators of the impulsivity-substance use relation: pathways for negative urgency, lack of premeditation, and sensation seeking.

PubMed

Adams, Zachary W; Kaiser, Alison J; Lynam, Donald R; Charnigo, Richard J; Milich, Richard

2012-07-01

Trait impulsivity is a reliable, robust predictor of risky, problematic alcohol use. Mounting evidence supports a multidimensional model of impulsivity, whereby several distinct traits serve as personality pathways to rash action. Different impulsivity-related traits may predispose individuals to drink for different reasons (e.g., to enhance pleasure, to cope with distress) and these different motives may, in turn, influence drinking behavior. Previous findings support such a mediational model for two well-studied traits: sensation seeking and lack of premeditation. This study addresses other impulsivity-related traits, including negative urgency. College students (N=432) completed questionnaires assessing personality, drinking motives, and multiple indicators of problematic drinking. Negative urgency, sensation seeking, and lack of premeditation were all significantly related to problematic drinking. When drinking motives were included in the model, direct effects for sensation seeking and lack of premeditation remained significant, and indirect effects of sensation seeking and lack of premeditation on problematic drinking were observed through enhancement motives. A distinct pathway was observed for negative urgency. Negative urgency bore a significant total effect on problematic drinking through both coping and enhancement motives. This study highlights unique motivational pathways through which different impulsive traits may operate, suggesting that interventions aimed at preventing or reducing problematic drinking should be tailored to individuals' personalities. For instance, individuals high in negative urgency may benefit from learning healthier strategies for coping with distress. Copyright © 2012 Elsevier Ltd. All rights reserved.

Drinking Motives as Mediators of the Impulsivity-Substance Use Relation: Pathways for Negative Urgency, Lack of Premeditation, and Sensation Seeking

PubMed Central

Adams, Zachary W.; Kaiser, Alison J.; Lynam, Donald R.; Charnigo, Richard J.; Milich, Richard

2012-01-01

Trait impulsivity is a reliable, robust predictor of risky, problematic alcohol use. Mounting evidence supports a multidimensional model of impulsivity, whereby several distinct traits serve as personality pathways to rash action. Different impulsivity-related traits may predispose individuals to drink for different reasons (e.g., to enhance pleasure, to cope with distress) and these different motives may, in turn, influence drinking behavior. Previous findings support such a mediational model for two well-studied traits: sensation seeking and lack of premeditation. This study addresses other impulsivity-related traits, including negative urgency. College students (N = 432) completed questionnaires assessing personality, drinking motives, and multiple indicators of problematic drinking. Negative urgency, sensation seeking, and lack of premeditation were all significantly related to problematic drinking. When drinking motives were included in the model, direct effects for sensation seeking and lack of premeditation remained significant, and indirect effects of sensation seeking and lack of premeditation on problematic drinking were observed through enhancement motives. A distinct pathway was observed for negative urgency. Negative urgency bore a significant total effect on problematic drinking through both coping and enhancement motives. This study highlights unique motivational pathways through which different impulsive traits may operate, suggesting that interventions aimed at preventing or reducing problematic drinking should be tailored to individuals' personalities. For instance, individuals high in negative urgency may benefit from learning healthier strategies for coping with distress. PMID:22472524

A Puzzle Unsolved: Failure to Observe Different Effects of God and Religion Primes on Intergroup Attitudes

PubMed Central

Ramsay, Jonathan E.; Tong, Eddie M. W.; Pang, Joyce S.; Chowdhury, Avijit

2016-01-01

Religious priming has been found to have both positive and negative consequences, and recent research suggests that the activation of God-related and community-related religious cognitions may cause outgroup prosociality and outgroup derogation respectively. The present research sought to examine whether reminders of God and religion have different effects on attitudes towards ingroup and outgroup members. Over two studies, little evidence was found for different effects of these two types of religious primes. In study 1, individuals primed with the words “religion”, “God” and a neutral control word evaluated both ingroup and outgroup members similarly, although a marginal tendency towards more negative evaluations of outgroup members by females exposed to religion primes was observed. In study 2, no significant differences in attitudes towards an outgroup member were observed between the God, religion, and neutral priming conditions. Furthermore, the gender effect observed in study 1 did not replicate in this second study. Possible explanations for these null effects are discussed. PMID:26812526

A Puzzle Unsolved: Failure to Observe Different Effects of God and Religion Primes on Intergroup Attitudes.

PubMed

Ramsay, Jonathan E; Tong, Eddie M W; Pang, Joyce S; Chowdhury, Avijit

2016-01-01

Religious priming has been found to have both positive and negative consequences, and recent research suggests that the activation of God-related and community-related religious cognitions may cause outgroup prosociality and outgroup derogation respectively. The present research sought to examine whether reminders of God and religion have different effects on attitudes towards ingroup and outgroup members. Over two studies, little evidence was found for different effects of these two types of religious primes. In study 1, individuals primed with the words "religion", "God" and a neutral control word evaluated both ingroup and outgroup members similarly, although a marginal tendency towards more negative evaluations of outgroup members by females exposed to religion primes was observed. In study 2, no significant differences in attitudes towards an outgroup member were observed between the God, religion, and neutral priming conditions. Furthermore, the gender effect observed in study 1 did not replicate in this second study. Possible explanations for these null effects are discussed.

Are Individual Differences in Reading Speed Related to Extrafoveal Visual Acuity and Crowding?

PubMed Central

Frömer, Romy; Dimigen, Olaf; Niefind, Florian; Krause, Niels; Kliegl, Reinhold; Sommer, Werner

2015-01-01

Readers differ considerably in their speed of self-paced reading. One factor known to influence fixation durations in reading is the preprocessing of words in parafoveal vision. Here we investigated whether individual differences in reading speed or the amount of information extracted from upcoming words (the preview benefit) can be explained by basic differences in extrafoveal vision—i.e., the ability to recognize peripheral letters with or without the presence of flanking letters. Forty participants were given an adaptive test to determine their eccentricity thresholds for the identification of letters presented either in isolation (extrafoveal acuity) or flanked by other letters (crowded letter recognition). In a separate eye-tracking experiment, the same participants read lists of words from left to right, while the preview of the upcoming words was manipulated with the gaze-contingent moving window technique. Relationships between dependent measures were analyzed on the observational level and with linear mixed models. We obtained highly reliable estimates both for extrafoveal letter identification (acuity and crowding) and measures of reading speed (overall reading speed, size of preview benefit). Reading speed was higher in participants with larger uncrowded windows. However, the strength of this relationship was moderate and it was only observed if other sources of variance in reading speed (e.g., the occurrence of regressive saccades) were eliminated. Moreover, the size of the preview benefit—an important factor in normal reading—was larger in participants with better extrafoveal acuity. Together, these results indicate a significant albeit moderate contribution of extrafoveal vision to individual differences in reading speed. PMID:25789812

Fluid intelligence and gross structural properties of the cerebral cortex in middle-aged and older adults: A multi-occasion longitudinal study.

PubMed

Yuan, Peng; Voelkle, Manuel C; Raz, Naftali

2018-05-15

According to Parieto-Frontal Integration Theory (P-FIT, Jung and Haier, 2007), individual differences in a circumscribed set of brain regions account for variations in general intelligence (g). The components of g, fluid (Gf) and crystallized (Gc) reasoning, exhibit distinct trajectories of age-related change. Because the brain also ages differentially, we hypothesized that age-related cognitive and neural changes would be coupled. In a sample of healthy middle-aged and older adults, we examined changes in Gf (operationalized by Cattell Culture Fair Test) and Gc (indexed by two vocabulary tests) as well as in structural properties of 19 brain regions. We fitted linear mixed models to the data collected on 73 healthy adults who participated in baseline assessment, with 43 returning for at least one follow-up, and 16 of them contributing four repeated assessments over seven years. We observed age differences as well as longitudinal decline in Gf, contrasted to a lack of age differences and stability in Gc. Cortical thickness and cortical volume exhibited significant age differences and longitudinal declines, which were accelerated in P-FIT regions. Gf (but not Gc) was associated with cortical thickness, but no such relationship was found for cortical volume. Uniformity of cognitive change (lack of reliable individual differences) precluded examination of the coupling between cognitive and brain changes. Cortical shrinkage was greater in high-Gc individuals, whereas in participants with higher Gf cortical volume slower volume shrinkage was observed. Copyright © 2018 Elsevier Inc. All rights reserved.

Predicting body temperature and activity of adult Polyommatus icarus using neural network models under current and projected climate scenarios.

PubMed

Howe, P D; Bryant, S R; Shreeve, T G

2007-10-01

We use field observations in two geographic regions within the British Isles and regression and neural network models to examine the relationship between microhabitat use, thoracic temperatures and activity in a widespread lycaenid butterfly, Polyommatus icarus. We also make predictions for future activity under climate change scenarios. Individuals from a univoltine northern population initiated flight with significantly lower thoracic temperatures than individuals from a bivoltine southern population. Activity is dependent on body temperature and neural network models of body temperature are better at predicting body temperature than generalized linear models. Neural network models of activity with a sole input of predicted body temperature (using weather and microclimate variables) are good predictors of observed activity and were better predictors than generalized linear models. By modelling activity under climate change scenarios for 2080 we predict differences in activity in relation to both regional differences of climate change and differing body temperature requirements for activity in different populations. Under average conditions for low-emission scenarios there will be little change in the activity of individuals from central-southern Britain and a reduction in northwest Scotland from 2003 activity levels. Under high-emission scenarios, flight-dependent activity in northwest Scotland will increase the greatest, despite smaller predicted increases in temperature and decreases in cloud cover. We suggest that neural network models are an effective way of predicting future activity in changing climates for microhabitat-specialist butterflies and that regional differences in the thermoregulatory response of populations will have profound effects on how they respond to climate change.

The relationship of alcohol use and physical activity from an ecologic perspective.

PubMed

Bigelow, April; Villarruel, Antonia; Ronis, David L

2014-01-01

To determine the predictors of alcohol use (AU) and their relationship to physical activity (PA) among adolescents and to examine differences among groups using an ecologic model. Cross sectional secondary analysis of 11,432 adolescents (51% 8th and 49% 10th graders). Attitude, perception of risk, and academic performance were the strongest predictors of AU. PA did not moderate, but it had a positive influence on AU in 10th graders. Differences were observed among groups. Nurses can address individual and school factors in an effort to decrease AU and guide nurses in creating an individualized plan. © 2013, Wiley Periodicals, Inc.

Social Anxiety, Affect, Cortisol Response and Performance on a Speech Task.

PubMed

Losiak, Wladyslaw; Blaut, Agata; Klosowska, Joanna; Slowik, Natalia

2016-01-01

Social anxiety is characterized by increased emotional reactivity to social stimuli, but results of studies focusing on affective reactions of socially anxious subjects in the situation of social exposition are inconclusive, especially in the case of endocrinological measures of affect. This study was designed to examine individual differences in endocrinological and affective reactions to social exposure as well as in performance on a speech task in a group of students (n = 44) comprising subjects with either high or low levels of social anxiety. Measures of salivary cortisol and positive and negative affect were taken before and after an impromptu speech. Self-ratings and observer ratings of performance were also obtained. Cortisol levels and negative affect increased in both groups after the speech task, and positive affect decreased; however, group × affect interactions were not significant. Assessments conducted after the speech task revealed that highly socially anxious participants had lower observer ratings of performance while cortisol increase and changes in self-reported affect were not related to performance. Socially anxious individuals do not differ from nonanxious individuals in affective reactions to social exposition, but reveal worse performance at a speech task. © 2015 S. Karger AG, Basel.

Controlling nosocomial infection based on structure of hospital social networks.

PubMed

Ueno, Taro; Masuda, Naoki

2008-10-07

Nosocomial infection (i.e. infection in healthcare facilities) raises a serious public health problem, as implied by the existence of pathogens characteristic to healthcare facilities such as methicillin-resistant Staphylococcus aureus and hospital-mediated outbreaks of influenza and severe acute respiratory syndrome. For general communities, epidemic modeling based on social networks is being recognized as a useful tool. However, disease propagation may occur in a healthcare facility in a manner different from that in a urban community setting due to different network architecture. We simulate stochastic susceptible-infected-recovered dynamics on social networks, which are based on observations in a hospital in Tokyo, to explore effective containment strategies against nosocomial infection. The observed social networks in the hospital have hierarchical and modular structure in which dense substructure such as departments, wards, and rooms, are globally but only loosely connected, and do not reveal extremely right-skewed distributions of the number of contacts per individual. We show that healthcare workers, particularly medical doctors, are main vectors (i.e. transmitters) of diseases on these networks. Intervention methods that restrict interaction between medical doctors and their visits to different wards shrink the final epidemic size more than intervention methods that directly protect patients, such as isolating patients in single rooms. By the same token, vaccinating doctors with priority rather than patients or nurses is more effective. Finally, vaccinating individuals with large betweenness centrality (frequency of mediating connection between pairs of individuals along the shortest paths) is superior to vaccinating ones with large connectedness to others or randomly chosen individuals, which was suggested by previous model studies.

Progranulin gene variation affects serum progranulin levels differently in Danish bipolar individuals compared with healthy controls.

PubMed

Buttenschøn, Henriette N; Nielsen, Marit N; Thotakura, Gangadaar; Lee, Chris W; Nykjær, Anders; Mors, Ole; Glerup, Simon

2017-06-01

The identification of peripheral biomarkers for bipolar disorder is of great importance and has the potential to improve diagnosis, treatment and prognosis. Recent studies have reported lower plasma progranulin levels in bipolar individuals compared with controls and association with single nucleotide polymorphisms (SNPs) within the progranulin gene (GRN). In the present study, we investigated the effect of GRN and sortilin (SORT1) gene variation on serum progranulin levels in bipolar individuals and controls. In a Danish cohort of individuals with bipolar disorder and controls, we analysed the serum progranulin level (nbipolar=80, ncontrols=76) and five SNPs located within GRN and two SNPs near the SORT1 gene encoding sortilin, a progranulin scavenger receptor known to affect circulating progranulin levels (nbipolar=166, ncontrols=186). We observed no significant difference in the serum progranulin level between cases and controls and none of the analysed SNPs located within GRN or close to SORT1 were associated with bipolar disorder. Crude and adjusted (adjusted for case-control status, sex and age) linear regression analyses showed no effect of any SNPs on the serum progranulin level. However, we observed that the mean serum progranulin level in cases and controls is affected differently depending on the genotypes of two SNPs within GRN (rs2879096 and rs4792938). The sample size is relatively small and detailed information on medication and polarity of the disorder is not available. No correction for multiple testing was performed. Our study suggests that the potential of progranulin as a biomarker for bipolar disorder is genotype dependent.

Spatial Positioning of All 24 Chromosomes in the Lymphocytes of Six Subjects: Evidence of Reproducible Positioning and Spatial Repositioning following DNA Damage with Hydrogen Peroxide and Ultraviolet B

PubMed Central

Kandukuri, Lakshmi; Quadri, Ameer; Becerra, Victor; Simpson, Joe Leigh

2015-01-01

The higher-order organization of chromatin is well-established, with chromosomes occupying distinct positions within the interphase nucleus. Chromatin is susceptible to, and constantly assaulted by both endogenous and exogenous threats. However, the effects of DNA damage on the spatial topology of chromosomes are hitherto, poorly understood. This study investigates the organization of all 24 human chromosomes in lymphocytes from six individuals prior to- and following in-vitro exposure to genotoxic agents: hydrogen peroxide and ultraviolet B. This study is the first to report reproducible distinct hierarchical radial organization of chromosomes with little inter-individual differences between subjects. Perturbed nuclear organization was observed following genotoxic exposure for both agents; however a greater effect was observed for hydrogen peroxide including: 1) More peripheral radial organization; 2) Alterations in the global distribution of chromosomes; and 3) More events of chromosome repositioning (18 events involving 10 chromosomes vs. 11 events involving 9 chromosomes for hydrogen peroxide and ultraviolet B respectively). Evidence is provided of chromosome repositioning and altered nuclear organization following in-vitro exposure to genotoxic agents, with notable differences observed between the two investigated agents. Repositioning of chromosomes following genotoxicity involved recurrent chromosomes and is most likely part of the genomes inherent response to DNA damage. The variances in nuclear organization observed between the two agents likely reflects differences in mobility and/or decondensation of chromatin as a result of differences in the type of DNA damage induced, chromatin regions targeted, and DNA repair mechanisms. PMID:25756782

Spatial positioning of all 24 chromosomes in the lymphocytes of six subjects: evidence of reproducible positioning and spatial repositioning following DNA damage with hydrogen peroxide and ultraviolet B.

PubMed

Ioannou, Dimitrios; Kandukuri, Lakshmi; Quadri, Ameer; Becerra, Victor; Simpson, Joe Leigh; Tempest, Helen G

2015-01-01

The higher-order organization of chromatin is well-established, with chromosomes occupying distinct positions within the interphase nucleus. Chromatin is susceptible to, and constantly assaulted by both endogenous and exogenous threats. However, the effects of DNA damage on the spatial topology of chromosomes are hitherto, poorly understood. This study investigates the organization of all 24 human chromosomes in lymphocytes from six individuals prior to- and following in-vitro exposure to genotoxic agents: hydrogen peroxide and ultraviolet B. This study is the first to report reproducible distinct hierarchical radial organization of chromosomes with little inter-individual differences between subjects. Perturbed nuclear organization was observed following genotoxic exposure for both agents; however a greater effect was observed for hydrogen peroxide including: 1) More peripheral radial organization; 2) Alterations in the global distribution of chromosomes; and 3) More events of chromosome repositioning (18 events involving 10 chromosomes vs. 11 events involving 9 chromosomes for hydrogen peroxide and ultraviolet B respectively). Evidence is provided of chromosome repositioning and altered nuclear organization following in-vitro exposure to genotoxic agents, with notable differences observed between the two investigated agents. Repositioning of chromosomes following genotoxicity involved recurrent chromosomes and is most likely part of the genomes inherent response to DNA damage. The variances in nuclear organization observed between the two agents likely reflects differences in mobility and/or decondensation of chromatin as a result of differences in the type of DNA damage induced, chromatin regions targeted, and DNA repair mechanisms.

Comparing the Scoring of Human Decomposition from Digital Images to Scoring Using On-site Observations.

PubMed

Dabbs, Gretchen R; Bytheway, Joan A; Connor, Melissa

2017-09-01

When in forensic casework or empirical research in-person assessment of human decomposition is not possible, the sensible substitution is color photographic images. To date, no research has confirmed the utility of color photographic images as a proxy for in situ observation of the level of decomposition. Sixteen observers scored photographs of 13 human cadavers in varying decomposition stages (PMI 2-186 days) using the Total Body Score system (total n = 929 observations). The on-site TBS was compared with recorded observations from digital color images using a paired samples t-test. The average difference between on-site and photographic observations was -0.20 (t = -1.679, df = 928, p = 0.094). Individually, only two observers, both students with <1 year of experience, demonstrated TBS statistically significantly different than the on-site value, suggesting that with experience, observations of human decomposition based on digital images can be substituted for assessments based on observation of the corpse in situ, when necessary. © 2017 American Academy of Forensic Sciences.

Shared liking and association valence for representational art but not abstract art.

PubMed

Schepman, Astrid; Rodway, Paul; Pullen, Sarah J; Kirkham, Julie

2015-01-01

We examined the finding that aesthetic evaluations are more similar across observers for representational images than for abstract images. It has been proposed that a difference in convergence of observers' tastes is due to differing levels of shared semantic associations (Vessel & Rubin, 2010). In Experiment 1, student participants rated 20 representational and 20 abstract artworks. We found that their judgments were more similar for representational than abstract artworks. In Experiment 2, we replicated this finding, and also found that valence ratings given to associations and meanings provided in response to the artworks converged more across observers for representational than for abstract art. Our empirical work provides insight into processes that may underlie the observation that taste for representational art is shared across individual observers, while taste for abstract art is more idiosyncratic.

Distinctive laterality of neural networks supporting action understanding in left- and right-handed individuals: An EEG coherence study.

PubMed

Kelly, Rachel; Mizelle, J C; Wheaton, Lewis A

2015-08-01

Prior work has demonstrated that perspective and handedness of observed actions can affect action understanding differently in right and left-handed persons, suggesting potential differences in the neural networks underlying action understanding between right and left-handed individuals. We sought to evaluate potential differences in these neural networks using electroencephalography (EEG). Right- and left-handed participants observed images of tool-use actions from egocentric and allocentric perspectives, with right- and left-handed actors performing the actions. Participants judged the outcome of the observed actions, and response accuracy and latency were recorded. Behaviorally, the highest accuracy and shortest latency was found in the egocentric perspective for right- and left-handed observers. Handedness of subject showed an effect on accuracy and latency also, where right-handed observers were faster to respond than left-handed observers, but on average were less accurate. Mu band (8-10 Hz) cortico-cortical coherence analysis indicated that right-handed observers have coherence in the motor dominant left parietal-premotor networks when looking at an egocentric right or allocentric left hands. When looking in an egocentric perspective at a left hand or allocentric right hand, coherence was lateralized to right parietal-premotor areas. In left-handed observers, bilateral parietal-premotor coherence patterns were observed regardless of actor handedness. These findings suggest that the cortical networks involved in understanding action outcomes are dependent on hand dominance, and notably right handed participants seem to utilize motor systems based on the limb seen performing the action. The decreased accuracy for right-handed participants on allocentric images could be due to asymmetrical lateralization of encoding action and motoric dominance, which may interfere with translating allocentric limb action outcomes. Further neurophysiological studies will determine the specific processes of how left- and right-handed participants understand actions. Copyright © 2015 Elsevier Ltd. All rights reserved.

Cannabis-related episodic memory deficits and hippocampal morphological differences in healthy individuals and schizophrenia subjects.

PubMed

Smith, Matthew J; Cobia, Derin J; Reilly, James L; Gilman, Jodi M; Roberts, Andrea G; Alpert, Kathryn I; Wang, Lei; Breiter, Hans C; Csernansky, John G

2015-09-01

Cannabis use has been associated with episodic memory (EM) impairments and abnormal hippocampus morphology among both healthy individuals and schizophrenia subjects. Considering the hippocampus' role in EM, research is needed to evaluate the relationship between cannabis-related hippocampal morphology and EM among healthy and clinical groups. We examined differences in hippocampus morphology between control and schizophrenia subjects with and without a past (not current) cannabis use disorder (CUD). Subjects group-matched on demographics included 44 healthy controls (CON), 10 subjects with a CUD history (CON-CUD), 28 schizophrenia subjects with no history of substance use disorders (SCZ), and 15 schizophrenia subjects with a CUD history (SCZ-CUD). Large-deformation, high-dimensional brain mapping with MRI produced surface-based representations of the hippocampus that were compared across all four groups and correlated with EM and CUD history. Surface maps of the hippocampus were generated to visualize morphological differences. CON-CUD and SCZ-CUD were characterized by distinct cannabis-related hippocampal shape differences and parametric deficits in EM performance. Shape differences observed in CON-CUD were associated with poorer EM performance, while shape differences observed in SCZ-CUD were associated with a longer duration of CUD and shorter duration of CUD remission. A past history of CUD may be associated with notable differences in hippocampal morphology and EM impairments among adults with and without schizophrenia. Although the results may be compatible with a causal hypothesis, we must consider that the observed cannabis-related shape differences in the hippocampus could also be explained as biomarkers of a neurobiological susceptibility to poor memory or the effects of cannabis. © 2015 Wiley Periodicals, Inc.

[Estimating survival of thrushes: modeling capture-recapture probabilities].

PubMed

Burskiî, O V

2011-01-01

The stochastic modeling technique serves as a way to correctly separate "return rate" of marked animals into survival rate (phi) and capture probability (p). The method can readily be used with the program MARK freely distributed through Internet (Cooch, White, 2009). Input data for the program consist of "capture histories" of marked animals--strings of units and zeros indicating presence or absence of the individual among captures (or sightings) along the set of consequent recapture occasions (e.g., years). Probability of any history is a product of binomial probabilities phi, p or their complements (1 - phi) and (1 - p) for each year of observation over the individual. Assigning certain values to parameters phi and p, one can predict the composition of all individual histories in the sample and assess the likelihood of the prediction. The survival parameters for different occasions and cohorts of individuals can be set either equal or different, as well as recapture parameters can be set in different ways. There is a possibility to constraint the parameters, according to the hypothesis being tested, in the form of a specific model. Within the specified constraints, the program searches for parameter values that describe the observed composition of histories with the maximum likelihood. It computes the parameter estimates along with confidence limits and the overall model likelihood. There is a set of tools for testing the model goodness-of-fit under assumption of equality of survival rates among individuals and independence of their fates. Other tools offer a proper selection among a possible variety of models, providing the best parity between details and precision in describing reality. The method was applied to 20-yr recapture and resighting data series on 4 thrush species (genera Turdus, Zoothera) breeding in the Yenisei River floodplain within the middle taiga subzone. The capture probabilities were quite independent of observational efforts fluctuations while differing significantly between the species and sexes. The estimates of adult survival rate, obtained for the Siberian migratory populations, were lower than those for sedentary populations from both the tropics and intermediate latitudes with marine climate (data by Ricklefs, 1997). Two factors, the average temperature influencing birds during their annual movements, and climatic seasonality (temperature difference between summer and winter) in the breeding area, fit the latitudinal pattern of survival most closely (R2 = 0.90). Final survival of migrants reflects an adaptive life history compromise for use of superabundant resources in breeding area at the cost of avoidance of severe winter conditions.

The Ontogenetic Osteohistology of Tenontosaurus tilletti

PubMed Central

Werning, Sarah

2012-01-01

Tenontosaurus tilletti is an ornithopod dinosaur known from the Early Cretaceous (Aptian-Albian) Cloverly and Antlers formations of the Western United States. It is represented by a large number of specimens spanning a number of ontogenetic stages, and these specimens have been collected across a wide geographic range (from central Montana to southern Oklahoma). Here I describe the long bone histology of T. tilletti and discuss histological variation at the individual, ontogenetic and geographic levels. The ontogenetic pattern of bone histology in T. tilletti is similar to that of other dinosaurs, reflecting extremely rapid growth early in life, and sustained rapid growth through sub-adult ontogeny. But unlike other iguanodontians, this dinosaur shows an extended multi-year period of slow growth as skeletal maturity approached. Evidence of termination of growth (e.g., an external fundamental system) is observed in only the largest individuals, although other histological signals in only slightly smaller specimens suggest a substantial slowing of growth later in life. Histological differences in the amount of remodeling and the number of lines of arrested growth varied among elements within individuals, but bone histology was conservative across sampled individuals of the species, despite known paleoenvironmental differences between the Antlers and Cloverly formations. The bone histology of T. tilletti indicates a much slower growth trajectory than observed for other iguanodontians (e.g., hadrosaurids), suggesting that those taxa reached much larger sizes than Tenontosaurus in a shorter time. PMID:22470454

Bilateral Proprioceptive Evaluation in Individuals With Unilateral Chronic Ankle Instability

PubMed Central

Sousa, Andreia S. P.; Leite, João; Costa, Bianca; Santos, Rubim

2017-01-01

Context: Despite extensive research on chronic ankle instability, the findings regarding proprioception have been conflicting and focused only on the injured limb. Also, the different components of proprioception have been evaluated in isolation. Objective: To evaluate bilateral ankle proprioception in individuals with unilateral ankle instability. Design: Cohort study. Setting: Research laboratory center in a university. Patients or Other Participants: Twenty-four individuals with a history of unilateral ankle sprain and chronic ankle instability (mechanical ankle instability group, n = 10; functional ankle instability [FAI] group, n = 14) and 20 controls. Main Outcome Measure(s): Ankle active and passive joint position sense, kinesthesia, and force sense. Results: We observed a significant interaction between the effects of limb and group for kinesthesia (F = 3.27, P = .049). Increased error values were observed in the injured limb of the FAI group compared with the control group (P = .031, Cohen d = 0.47). Differences were also evident for force sense (F = 9.31, P < .001): the FAI group demonstrated increased error versus the control group (injured limb: P < .001, Cohen d = 1.28; uninjured limb: P = .009, Cohen d = 0.89) and the mechanical ankle instability group (uninjured limb: P = .023, Cohen d = 0.76). Conclusions: Individuals with unilateral FAI had increased error ipsilaterally (injured limb) for inversion movement detection (kinesthesia) and evertor force sense and increased error contralaterally (uninjured limb) for evertor force sense. PMID:28318316

New reconstruction of the sunspot group numbers since 1739 using direct calibration and "backbone" methods

NASA Astrophysics Data System (ADS)

Chatzistergos, Theodosios; Usoskin, Ilya G.; Kovaltsov, Gennady A.; Krivova, Natalie A.; Solanki, Sami K.

2017-06-01

Context. The group sunspot number (GSN) series constitute the longest instrumental astronomical database providing information on solar activity. This database is a compilation of observations by many individual observers, and their inter-calibration has usually been performed using linear rescaling. There are multiple published series that show different long-term trends for solar activity. Aims: We aim at producing a GSN series, with a non-linear non-parametric calibration. The only underlying assumptions are that the differences between the various series are due to different acuity thresholds of the observers, and that the threshold of each observer remains constant throughout the observing period. Methods: We used a daisy chain process with backbone (BB) observers and calibrated all overlapping observers to them. We performed the calibration of each individual observer with a probability distribution function (PDF) matrix constructed considering all daily values for the overlapping period with the BB. The calibration of the BBs was carried out in a similar manner. The final series was constructed by merging different BB series. We modelled the propagation of errors straightforwardly with Monte Carlo simulations. A potential bias due to the selection of BBs was investigated and the effect was shown to lie within the 1σ interval of the produced series. The exact selection of the reference period was shown to have a rather small effect on our calibration as well. Results: The final series extends back to 1739 and includes data from 314 observers. This series suggests moderate activity during the 18th and 19th century, which is significantly lower than the high level of solar activity predicted by other recent reconstructions applying linear regressions. Conclusions: The new series provides a robust reconstruction, based on modern and non-parametric methods, of sunspot group numbers since 1739, and it confirms the existence of the modern grand maximum of solar activity in the second half of the 20th century. Values of the group sunspot number series are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/602/A69

Order Matters: The Order of Somatic Mutations Influences Cancer Evolution.

PubMed

Kent, David G; Green, Anthony R

2017-04-03

Cancers evolve as a consequence of multiple somatic lesions, with competition between subclones and sequential subclonal evolution. Some driver mutations arise either early or late in the evolution of different individual tumors, suggesting that the final malignant properties of a subclone reflect the sum of mutations acquired rather than the order in which they arose. However, very little is known about the cellular consequences of altering the order in which mutations are acquired. Recent studies of human myeloproliferative neoplasms show that the order in which individual mutations are acquired has a dramatic impact on the cell biological and molecular properties of tumor-initiating cells. Differences in clinical presentation, complications, and response to targeted therapy were all observed and implicate mutation order as an important player in cancer biology. These observations represent the first demonstration that the order of mutation acquisition influences stem and progenitor cell behavior and clonal evolution in any cancer. Thus far, the impact of different mutation orders has only been studied in hematological malignancies, and analogous studies of solid cancers are now required. Copyright © 2017 Cold Spring Harbor Laboratory Press; all rights reserved.

The effects of sex, sexual orientation, and digit ratio (2D:4D) on mental rotation performance.

PubMed

Peters, Michael; Manning, John T; Reimers, Stian

2007-04-01

In spite of the reduced level of experimental control, this large scale study brought some clarity into the relation between mental rotation task (MRT) performance and a number of variables where contradictory associations had previously been reported in the literature. Clear sex differences in MRT were observed for a sample of 134,317 men and 120,783 women, with men outperforming women. There were also MRT differences as a function of sexual orientation: heterosexual men performed better than homosexual men and homosexual women performed better than heterosexual women. Although bisexual men performed better than homosexual men but less well than heterosexual men, no significant differences were observed between bisexual and homosexual women. MRT performance in both men and women peaked in the 20-30 year range, and declined significantly and markedly thereafter. Both men and women showed a significant negative correlation between left and right digit finger ratio and MRT scores, such that individuals with smaller digit ratios (relatively longer ring finger than index finger) performed better than individuals with larger digit ratios.

Individual Differences in Nonverbal Number Discrimination Correlate with Event-Related Potentials and Measures of Probabilistic Reasoning

ERIC Educational Resources Information Center

Paulsen, David J.; Woldorff, Marty G.; Brannon, Elizabeth M.

2010-01-01

The current study investigated the neural activity patterns associated with numerical sensitivity in adults. Event-related potentials (ERPs) were recorded while adults observed sequentially presented display arrays (S1 and S2) of non-symbolic numerical stimuli (dots) and made same/different judgments of these stimuli by pressing a button only when…

Dynamical origins of the community structure of an online multi-layer society

NASA Astrophysics Data System (ADS)

Klimek, Peter; Diakonova, Marina; Eguíluz, Víctor M.; San Miguel, Maxi; Thurner, Stefan

2016-08-01

Social structures emerge as a result of individuals managing a variety of different social relationships. Societies can be represented as highly structured dynamic multiplex networks. Here we study the dynamical origins of the specific community structures of a large-scale social multiplex network of a human society that interacts in a virtual world of a massive multiplayer online game. There we find substantial differences in the community structures of different social actions, represented by the various layers in the multiplex network. Community sizes distributions are either fat-tailed or appear to be centered around a size of 50 individuals. To understand these observations we propose a voter model that is built around the principle of triadic closure. It explicitly models the co-evolution of node- and link-dynamics across different layers of the multiplex network. Depending on link and node fluctuation probabilities, the model exhibits an anomalous shattered fragmentation transition, where one layer fragments from one large component into many small components. The observed community size distributions are in good agreement with the predicted fragmentation in the model. This suggests that several detailed features of the fragmentation in societies can be traced back to the triadic closure processes.

Worldwide end-of-life practice for patients in ICUs.

PubMed

Wong, Wai-Tat; Phua, Jason; Joynt, Gavin M

2018-04-01

Published data and practice recommendations on end-of-life (EOL) generally reflect Western practice frameworks. Understanding worldwide practices is important because improving economic conditions are promoting rapid expansion of intensive care services in many previously disadvantaged regions, and increasing migration has promoted a new cultural diversity previously predominantly unicultural societies. This review explores current knowledge of similarities and differences in EOL practice between regions and possible causes and implications of these differences. Recent observational and survey data shows a marked variability in the practice of withholding and withdrawing life sustaining therapy worldwide. Some evidence supports the view that culture, religion, and socioeconomic factors influence EOL practice, and individually or together account for differences observed. There are also likely to be commonly desired values and expectations for EOL practice, and recent attempts at establishing where worldwide consensus may lie have improved our understanding of shared values and practices. Awareness of differences, understanding their likely complex causes, and using this knowledge to inform individualized care at EOL is likely to improve the quality of care for patients. Further research should clarify the causes of EOL practice variability, monitor trends, and objectively evaluate the quality of EOL practice worldwide.

The role of one-shot learning in #TheDress.

PubMed

Drissi Daoudi, Leila; Doerig, Adrien; Parkosadze, Khatuna; Kunchulia, Marina; Herzog, Michael H

2017-03-01

#TheDress is remarkable in two aspects. First, there is a bimodal split of the population in the perception of the dress's colors (white/gold vs. black/blue). Second, whereas interobserver variance is high, intra-observer variance is low, i.e., the percept rarely switches in a given individual. There are two plausible routes of explanations: either one-shot learning during the first presentation of the image splits observers into two different, stable populations, or the differences are caused by stable traits of observers, such as different visual systems. Here, we hid large parts of the image by white occluders. The majority of naïve participants perceived the dress as black and blue. With black occluders, the majority of observers perceived the dress as white and gold. The percept did not change when we subsequently presented the full image, arguing for a crucial role of one-shot learning. Next, we investigated whether the first fixation determines the perceived color in naïve observers. We found no such effect. It remains thus a puzzling question where the source of variability in the different percepts comes from.

Effects of complete monocular deprivation in visuo-spatial memory.

PubMed

Cattaneo, Zaira; Merabet, Lotfi B; Bhatt, Ela; Vecchi, Tomaso

2008-09-30

Monocular deprivation has been associated with both specific deficits and enhancements in visual perception and processing. In this study, performance on a visuo-spatial memory task was compared in congenitally monocular individuals and sighted control individuals viewing monocularly (i.e., patched) and binocularly. The task required the individuals to view and memorize a series of target locations on two-dimensional matrices. Overall, congenitally monocular individuals performed worse than sighted individuals (with a specific deficit in simultaneously maintaining distinct spatial representations in memory), indicating that the lack of binocular visual experience affects the way visual information is represented in visuo-spatial memory. No difference was observed between the monocular and binocular viewing control groups, suggesting that early monocular deprivation affects the development of cortical mechanisms mediating visuo-spatial cognition.

An international comparative family medicine study of the Transition Project data from the Netherlands, Malta, Japan and Serbia. An analysis of diagnostic odds ratios aggregated across age bands, years of observation and individual practices.

PubMed

Soler, Jean K; Okkes, Inge; Oskam, Sibo; van Boven, Kees; Zivotic, Predrag; Jevtic, Milan; Dobbs, Frank; Lamberts, Henk

2012-06-01

This is a study of the process of diagnosis in family medicine (FM) in four practice populations from the Netherlands, Malta, Serbia and Japan. Diagnostic odds ratios (ORs) for common reasons for encounter (RfEs) and episode titles are used to study the process of diagnosis in international FM and to test the assumption that data can be aggregated across different age bands, practices and years of observation. Participating family doctors (FDs) recorded details of all their patient contacts in an episode of care (EoC) structure using the International Classification of Primary Care (ICPC). RfEs presented by the patient and the diagnostic labels (EoC titles) recorded for each encounter were classified with ICPC. The relationships between RfEs and episode titles were expressed as ORs using Bayesian probability analysis to calculate the posterior (post-test) odds of an episode title given an RfE, at the start of a new EoC. The distributions of diagnostic ORs from the four population databases are tabled across age groups, years of observation and practices. There is a lot of congruence in diagnostic process and concepts between populations, across age groups, years of observation and FD practices, despite differences in the strength of such diagnostic associations. There is particularly little variability of diagnostic ORs across years of observation and between individual FD practices. Given our findings, it makes sense to aggregate diagnostic data from different FD practices and years of observation. Our findings support the existence of common core diagnostic concepts in international FM.

Capturing the complexity: Content, type, and amount of instruction and quality of the classroom learning environment synergistically predict third graders’ vocabulary and reading comprehension outcomes

PubMed Central

Connor, Carol McDonald; Spencer, Mercedes; Day, Stephanie L.; Giuliani, Sarah; Ingebrand, Sarah W.; McLean, Leigh; Morrison, Frederick J.

2014-01-01

We examined classrooms as complex systems that affect students’ literacy learning through interacting effects of content and amount of time individual students spent in literacy instruction along with the global quality of the classroom-learning environment. We observed 27 third grade classrooms serving 315 target students using two different observation systems. The first assessed instruction at a more micro-level; specifically, the amount of time individual students spent in literacy instruction defined by the type of instruction, role of the teacher, and content. The second assessed the quality of the classroom-learning environment at a more macro level focusing on classroom organization, teacher responsiveness, and support for vocabulary and language. Results revealed that both global quality of the classroom learning environment and time individual students spent in specific types of literacy instruction covering specific content interacted to predict students’ comprehension and vocabulary gains whereas neither system alone did. These findings support a dynamic systems model of how individual children learn in the context of classroom literacy instruction and the classroom-learning environment, which can help to improve observations systems, advance research, elevate teacher evaluation and professional development, and enhance student achievement. PMID:25400293

Error in geometric morphometric data collection: Combining data from multiple sources.

PubMed

Robinson, Chris; Terhune, Claire E

2017-09-01

This study compares two- and three-dimensional morphometric data to determine the extent to which intra- and interobserver and intermethod error influence the outcomes of statistical analyses. Data were collected five times for each method and observer on 14 anthropoid crania using calipers, a MicroScribe, and 3D models created from NextEngine and microCT scans. ANOVA models were used to examine variance in the linear data at the level of genus, species, specimen, observer, method, and trial. Three-dimensional data were analyzed using geometric morphometric methods; principal components analysis was employed to examine how trials of all specimens were distributed in morphospace and Procrustes distances among trials were calculated and used to generate UPGMA trees to explore whether all trials of the same individual grouped together regardless of observer or method. Most variance in the linear data was at the genus level, with greater variance at the observer than method levels. In the 3D data, interobserver and intermethod error were similar to intraspecific distances among Callicebus cupreus individuals, with interobserver error being higher than intermethod error. Generally, taxa separate well in morphospace, with different trials of the same specimen typically grouping together. However, trials of individuals in the same species overlapped substantially with one another. Researchers should be cautious when compiling data from multiple methods and/or observers, especially if analyses are focused on intraspecific variation or closely related species, as in these cases, patterns among individuals may be obscured by interobserver and intermethod error. Conducting interobserver and intermethod reliability assessments prior to the collection of data is recommended. © 2017 Wiley Periodicals, Inc.

Shape of the orbital opening: individual characterization and analysis of variability in modern humans, Gorilla gorilla, and Pan troglodytes.

PubMed

Schmittbuhl, M; Le Minor, J M; Allenbach, B; Schaaf, A

1999-05-01

The description of the human orbital shape is principally qualitative in the classical literature, and characterised by adjectives such as circular, rectangular or quadrangular. In order to provide a precise quantification and interpretation of this shape, a study based on automatic image analysis and Fourier analysis was carried out on 45 human skulls (30 males, 15 females), and for comparison on 61 skulls of Gorilla gorilla (40 males, 21 females), and 34 skulls of Pan troglodytes (20 males, 14 females). Sexual dimorphism in the shape of the orbital opening was not demonstrated. Its dominant morphological features could be characterized by Fourier analysis; elliptical elongation and quadrangularity were dominant morphological features of the shape of the orbital opening in the three species. Elliptical elongation was more marked in humans and Pan, whereas quadrangularity was particularly emphasized in Gorilla. An intraspecific variability of the shape of the orbital opening existed in humans, Gorilla and Pan, and seemed close in the three species. Interspecific partition between humans, Gorilla and Pan was demonstrated despite the variability observed in the three species studied. Interspecific differences between Gorilla and the Pan-humans group were principally explained by the differences in quadrangularity, and by differences in orientation of triangularity and pentagonality. Differences in the shape of the orbital opening between humans and Pan were principally explained by differences in hexagonality, and by differences in orientation of quadrangularity. A closeness of shape between some humans and some individuals in Pan and, to a lesser degree, with some individuals in Gorilla was observed, demonstrating the existence of a morphological continuum of the shape of the orbital opening in hominoids.

Is an index of co-occurring unhealthy lifestyles suitable for understanding migrant health?

PubMed

Feng, Xiaoqi; Astell-Burt, Thomas; Kolt, Gregory S

2014-12-01

This study investigated variation in unhealthy lifestyles within Australia according to where people were born. Multilevel linear regression models were used to explore variation in co-occurring unhealthy lifestyles (from 0 to 8) constructed from responses to tobacco smoking, alcohol consumption, moderate-to-vigorous physical activity and a range of dietary indicators for 217,498 adults born in 22 different countries now living in Australia. Models were adjusted for socio-economic variables. Data was from the 45 and Up Study (2006-2009). Further analyses involved multilevel logistic regression to examine country-of-birth patterning of each individual unhealthy lifestyle. Small differences in the co-occurrence of unhealthy lifestyles were observed by country of birth, ranging from 3.1 (Philippines) to 3.8 (Russia). More substantial variation was observed for each individual unhealthy lifestyle. Smoking and alcohol ranged from 7.3% and 4.2% (both China) to 28.5% (Lebanon) and 30.8% (Ireland) respectively. Non-adherence to physical activity guidelines was joint-highest among participants born in Japan and China (both 74.5%), but lowest among those born in Scandinavian countries (52.5%). Substantial variation in meeting national dietary guidelines was also evident between participants born in different countries. The growing trend for constructing unhealthy lifestyle indices can hide important variation in individual unhealthy lifestyles by country of birth. Copyright © 2014. Published by Elsevier Inc.

Dynamics of a nuclear invasion

NASA Astrophysics Data System (ADS)

Roper, Marcus; Simonin, Anna; Glass, N. Louise

2009-11-01

Filamentous fungi grow as a network of continuous interconnected tubes, containing nuclei that move freely through a shared cytoplasm. Wild fungi are frequently chimerical: two nuclei from the same physiological individual may be genetically different. Such internal diversity can arise either from spontaneous mutations during nuclear division, or by nuclear exchange when two individuals fuse, sharing their resources and organelles to become a single individual. This diversity is thought to be essential to adaptation in plant pathogens, allowing, for instance, an invading fungus to present many different genetic identities against its host's immune response. However, it is clear that the presence of multiple genetic lineages within the same physiological individual can also pose challenges - lineages that are present in growing hyphal tips will multiply preferentially. Nuclei must therefore be kept well mixed across a growing front. By applying models developed to describe mixing of fluids in microfluidic reactors to experimental observations of lineage mixing in a growing Neurospora crassa colony, we show how this mixing is achieved. In particular we analyze the individual contributions from interdigitation of hyphae and from nuclear transport.

Caffeine affects CD8+ lymphocyte apoptosis and migration differently in naïve and familiar individuals following moderate intensity exercise.

PubMed

Navalta, James W; Fedor, Elizabeth A; Schafer, Mark A; Lyons, T Scott; Tibana, Ramires A; Pereira, Guilherme B; Prestes, Jonato

2016-06-01

The purpose of this investigation was to determine the lymphocyte subset response to 30 min of moderate treadmill exercise during caffeine supplemented (6.0 mg.kg(-1)) and placebo conditions in caffeine-naïve and -familiar individuals. Seventeen individuals participated (caffeine-familiar = 8, caffeine-naïve = 9) completing two exercise bouts (caffeine supplemented and placebo control) 48 h apart in a counterbalanced and double-blinded fashion. Individuals were classified as follows: caffeine-naive <50 mg.d(-1) and caffeine-familiar >200 mg.d(-1) Whole blood samples were obtained at rest, 30 min after caffeine or placebo ingestion, immediately following exercise, and 1 h post exercise. Blood was used to analyze apoptosis (annexin V) and cellular migration (CX3CR1) responses in lymphocyte subsets (CD4+, CD8+, CD19+). Absolute changes from rest values were calculated and differences between conditions were determined through Chi-squared analysis with significance accepted at P <0.05. With regard to CD4+ and CD19+ lymphocytes, the interaction of caffeine and exercise did not affect naïve individuals to a greater extent immediately post exercise when compared to familiar, as similar apoptotic and migratory responses were observed (P >0.05). However, CD8+ lymphocyte cell death and migration responses were observed to be significantly greater at each sampling point in caffeine-familiar individuals (P <0.05). It is possible that chronic caffeine supplementation may prime CD8+ cell receptors for responsiveness to apoptosis and migration and the consequence of this form of immunosuppression in the post-exercise period should be determined. © The Author(s) 2015.

A linguistic comparison between auditory verbal hallucinations in patients with a psychotic disorder and in nonpsychotic individuals: Not just what the voices say, but how they say it.

PubMed

de Boer, J N; Heringa, S M; van Dellen, E; Wijnen, F N K; Sommer, I E C

2016-11-01

Auditory verbal hallucinations (AVH) in psychotic patients are associated with activation of right hemisphere language areas, although this hemisphere is non-dominant in most people. Language generated in the right hemisphere can be observed in aphasia patients with left hemisphere damage. It is called "automatic speech", characterized by low syntactic complexity and negative emotional valence. AVH in nonpsychotic individuals, by contrast, predominantly have a neutral or positive emotional content and may be less dependent on right hemisphere activity. We hypothesize that right hemisphere language characteristics can be observed in the language of AVH, differentiating psychotic from nonpsychotic individuals. 17 patients with a psychotic disorder and 19 nonpsychotic individuals were instructed to repeat their AVH verbatim directly upon hearing them. Responses were recorded, transcribed and analyzed for total words, mean length of utterance, proportion of grammatical utterances, proportion of negations, literal and thematic perseverations, abuses, type-token ratio, embeddings, verb complexity, noun-verb ratio, and open-closed class ratio. Linguistic features of AVH overall differed between groups F(13,24)=3.920, p=0.002; Pillai's Trace 0.680. AVH of psychotic patients compared with AVH of nonpsychotic individuals had a shorter mean length of utterance, lower verb complexity, and more verbal abuses and perseverations (all p<0.05). Other features were similar between groups. AVH of psychotic patients showed lower syntactic complexity and higher levels of repetition and abuses than AVH of nonpsychotic individuals. These differences are in line with a stronger involvement of the right hemisphere in the origination of AVH in patients than in nonpsychotic voice hearers. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of ancestry and common genetic variants on QT interval in African Americans.

PubMed

Smith, J Gustav; Avery, Christy L; Evans, Daniel S; Nalls, Michael A; Meng, Yan A; Smith, Erin N; Palmer, Cameron; Tanaka, Toshiko; Mehra, Reena; Butler, Anne M; Young, Taylor; Buxbaum, Sarah G; Kerr, Kathleen F; Berenson, Gerald S; Schnabel, Renate B; Li, Guo; Ellinor, Patrick T; Magnani, Jared W; Chen, Wei; Bis, Joshua C; Curb, J David; Hsueh, Wen-Chi; Rotter, Jerome I; Liu, Yongmei; Newman, Anne B; Limacher, Marian C; North, Kari E; Reiner, Alexander P; Quibrera, P Miguel; Schork, Nicholas J; Singleton, Andrew B; Psaty, Bruce M; Soliman, Elsayed Z; Solomon, Allen J; Srinivasan, Sathanur R; Alonso, Alvaro; Wallace, Robert; Redline, Susan; Zhang, Zhu-Ming; Post, Wendy S; Zonderman, Alan B; Taylor, Herman A; Murray, Sarah S; Ferrucci, Luigi; Arking, Dan E; Evans, Michele K; Fox, Ervin R; Sotoodehnia, Nona; Heckbert, Susan R; Whitsel, Eric A; Newton-Cheh, Christopher

2012-12-01

Ethnic differences in cardiac arrhythmia incidence have been reported, with a particularly high incidence of sudden cardiac death and low incidence of atrial fibrillation in individuals of African ancestry. We tested the hypotheses that African ancestry and common genetic variants are associated with prolonged duration of cardiac repolarization, a central pathophysiological determinant of arrhythmia, as measured by the electrocardiographic QT interval. First, individual estimates of African and European ancestry were inferred from genome-wide single-nucleotide polymorphism (SNP) data in 7 population-based cohorts of African Americans (n=12,097) and regressed on measured QT interval from ECGs. Second, imputation was performed for 2.8 million SNPs, and a genome-wide association study of QT interval was performed in 10 cohorts (n=13,105). There was no evidence of association between genetic ancestry and QT interval (P=0.94). Genome-wide significant associations (P<2.5 × 10(-8)) were identified with SNPs at 2 loci, upstream of the genes NOS1AP (rs12143842, P=2 × 10(-15)) and ATP1B1 (rs1320976, P=2 × 10(-10)). The most significant SNP in NOS1AP was the same as the strongest SNP previously associated with QT interval in individuals of European ancestry. Low probability values (P<10(-5)) were observed for SNPs at several other loci previously identified in genome-wide association studies in individuals of European ancestry, including KCNQ1, KCNH2, LITAF, and PLN. We observed no difference in duration of cardiac repolarization with global genetic indices of African American ancestry. In addition, our genome-wide association study extends the association of polymorphisms at several loci associated with repolarization in individuals of European ancestry to include individuals of African ancestry.

A systematic review and meta-analysis of lower limb neuromuscular alterations associated with knee osteoarthritis during level walking.

PubMed

Mills, Kathryn; Hunt, Michael A; Leigh, Ryan; Ferber, Reed

2013-08-01

Neuromuscular alterations are increasingly reported in individuals with knee osteoarthritis (KOA) during level walking. We aimed to determine which neuromuscular alterations are consistent in KOA individuals and how these may be influenced by osteoarthritis severity, varus alignment and/or joint laxity. Electronic databases were searched up to July 2012. Cross-sectional observational studies comparing lower-limb neuromuscular activity in individuals with KOA, healthy controls or with different KOA cohorts were included. Two reviewers assessed methodological quality. Effect sizes were used to quantify the magnitude of observed differences. Where studies were homogenous, effect sizes were pooled using a fixed-effects model. Fourteen studies examining neuromuscular alterations in indices of co-contraction, muscle amplitude and muscle activity duration were included. Data pooling revealed that moderate KOA individuals exhibit increased co-contraction of lateral knee muscles (ES 0.64 [0.3 to 0.97]) and moderately increased rectus femoris (ES 0.73 [0.23 to 1.22]), vastus lateralis (ES 0.77 [0.27 to 1.27]) and biceps femoris (ES 1.18 [0.67 to 1.7]) mean amplitude. Non-pooled data indicated prolonged activity of these muscles. Increased medial knee neuromuscular activity was prevalent for those exhibiting varus alignment and medial knee joint laxity. Interpretation Individuals with KOA exhibited increased co-contraction, amplitude and duration of lateral knee muscles regardless of disease severity, limb alignment or medial joint laxity. Individuals with severe disease, varus alignment and medial joint laxity demonstrate up-regulation of medial knee muscles. Future research investigating the efficacy of neuromuscular rehabilitation programs should consider the effect of simultaneous up-regulation of medial and lateral knee muscles on disease progression. © 2013.

Response variability of different anodal transcranial direct current stimulation intensities across multiple sessions.

PubMed

Ammann, Claudia; Lindquist, Martin A; Celnik, Pablo A

It is well known that transcranial direct current stimulation (tDCS) is capable of modulating corticomotor excitability. However, a source of growing concern has been the observed inter- and intra-individual variability of tDCS-responses. Recent studies have assessed whether individuals respond in a predictable manner across repeated sessions of anodal tDCS (atDCS). The findings of these investigations have been inconsistent, and their methods have some limitations (i.e. lack of sham condition or testing only one tDCS intensity). To study inter- and intra-individual variability of atDCS effects at two different intensities on primary motor cortex (M1) excitability. Twelve subjects participated in a crossover study testing 7-min atDCS over M1 in three separate conditions (2 mA, 1 mA, sham) each repeated three times separated by 48 h. Motor evoked potentials were recorded before and after stimulation (up to 30min). Time of testing was maintained consistent within participants. To estimate the reliability of tDCS effects across sessions, we calculated the Intra-class Correlation Coefficient (ICC). AtDCS at 2 mA, but not 1 mA, significantly increased cortical excitability at the group level in all sessions. The overall ICC revealed fair to high reliability of tDCS effects for multiple sessions. Given that the distribution of responses showed important variability in the sham condition, we established a Sham Variability-Based Threshold to classify responses and to track individual changes across sessions. Using this threshold an intra-individual consistent response pattern was then observed only for the 2 mA condition. 2 mA anodal tDCS results in consistent intra- and inter-individual increases of M1 excitability. Copyright © 2017 Elsevier Inc. All rights reserved.

On the relationship between human search strategies, conspicuity, and search performance

NASA Astrophysics Data System (ADS)

Hogervorst, Maarten A.; Bijl, Piet; Toet, Alexander

2005-05-01

We determined the relationship between search performance with a limited field of view (FOV) and several scanning- and scene parameters in human observer experiments. The observers (38 trained army scouts) searched through a large search sector for a target (a camouflaged person) on a heath. From trial to trial the target appeared at a different location. With a joystick the observers scanned through a panoramic image (displayed on a PC-monitor) while the scan path was registered. Four conditions were run differing in sensor type (visual or thermal infrared) and window size (large or small). In conditions with a small window size the zoom option could be used. Detection performance was highly dependent on zoom factor and deteriorated when scan speed increased beyond a threshold value. Moreover, the distribution of scan speeds scales with the threshold speed. This indicates that the observers are aware of their limitations and choose a (near) optimal search strategy. We found no correlation between the fraction of detected targets and overall search time for the individual observers, indicating that both are independent measures of individual search performance. Search performance (fraction detected, total search time, time in view for detection) was found to be strongly related to target conspicuity. Moreover, we found the same relationship between search performance and conspicuity for visual and thermal targets. This indicates that search performance can be predicted directly by conspicuity regardless of the sensor type.

Does Human Body Odor Represent a Significant and Rewarding Social Signal to Individuals High in Social Openness?

PubMed Central

Lübke, Katrin T.; Croy, Ilona; Hoenen, Matthias; Gerber, Johannes; Pause, Bettina M.; Hummel, Thomas

2014-01-01

Across a wide variety of domains, experts differ from novices in their response to stimuli linked to their respective field of expertise. It is currently unknown whether similar patterns can be observed with regard to social expertise. The current study therefore focuses on social openness, a central social skill necessary to initiate social contact. Human body odors were used as social cues, as they inherently signal the presence of another human being. Using functional MRI, hemodynamic brain responses to body odors of women reporting a high (n = 14) or a low (n = 12) level of social openness were compared. Greater activation within the inferior frontal gyrus and the caudate nucleus was observed in high socially open individuals compared to individuals low in social openness. With the inferior frontal gyrus being a crucial part of the human mirror neuron system, and the caudate nucleus being implicated in social reward, it is discussed whether human body odor might constitute more of a significant and rewarding social signal to individuals high in social openness compared to individuals low in social openness process. PMID:24718308

Does enhanced insulin sensitivity improve sleep measures in patients with obstructive sleep apnea: A randomized, placebo-controlled pilot study

PubMed Central

Liu, Alice; Kim, Sun H.; Ariel, Danit; Abbasi, Fahim; Lamendola, Cindy; Cardell, James; Xu, Shiming; Patel, Shailja; Tomasso, Vanessa; Mojaddidi, Hafasa; Grove, Kaylene; Tsao, Philip S.; Kushida, Clete A.; Reaven, Gerald M.

2016-01-01

Background High fasting insulin levels have been reported to predict development of observed apneas, suggesting that insulin resistance may contribute to the pathogenesis of obstructive sleep apnea (OSA). The study aim was to determine whether enhancing insulin sensitivity in individuals with OSA would improve sleep measures. Patients/Methods Insulin-resistant, nondiabetic individuals with untreated OSA were randomized (2:1) to pioglitazone (45mg/day) or placebo for 8 weeks in this single-blind study. All individuals had repeat measurements pertaining to sleep (overnight polysomnography and Functional Outcomes of Sleep Questionnaire) and insulin action (insulin suppression test). Results Forty-five overweight/obese men and women with moderate/severe OSA were randomized to pioglitazone (n=30) or placebo (n=15). Although insulin sensitivity increased 31% among pioglitazone-treated as compared to no change among individuals receiving placebo ((p<0.001 for between-group difference), no improvements in quantitative or qualitative sleep measurements were observed. Conclusions Pioglitazone administration increased insulin sensitivity in otherwise untreated individuals with OSA, without any change in polysomnographic sleep measures over an 8-week period. These findings do not support a causal role for insulin resistance in the pathogenesis of OSA. PMID:27544837

Differences in attention to food and food intake between overweight/obese and normal-weight females under conditions of hunger and satiety.

PubMed

Nijs, Ilse M T; Muris, Peter; Euser, Anja S; Franken, Ingmar H A

2010-04-01

Starting from an addiction model of obesity, the present study examined differences in attention for food-related stimuli and food intake between overweight/obese and normal-weight women under conditions of hunger and satiety. Twenty-six overweight/obese (BMI: 30.00+/-4.62) and 40 normal-weight (BMI: 20.63+/-1.14) females were randomly assigned to a condition of hunger or satiety. Three indexes of attention were employed, all including pictures of food items: an eye-tracking paradigm (gaze direction and duration), a visual probe task (reaction times), and a recording of electrophysiological brain activity (amplitude of the P300 event-related potential). In addition, the acute food intake of participants was assessed using a bogus taste task. In general, an attentional bias towards food pictures was found in all participants. No differences between groups or conditions were observed in the eye-tracking data. The visual probe task revealed an enhanced automatic orientation towards food cues in hungry versus satiated, and in overweight/obese versus normal-weight individuals, but no differences between groups or conditions in maintained attention. The P300 amplitude showed that only in normal-weight participants the intentional allocation of attention to food pictures was enhanced in hunger versus satiety. In hungry overweight/obese participants, the P300 bias for food pictures was not clearly present, although an increased food intake was observed especially in this group. In conclusion, various attention-related tasks yielded various results, suggesting that they measure different underlying processes. Strikingly, overweight/obese individuals appear to automatically direct their attention to food-related stimuli, to a greater extent than normal-weight individuals, particularly when food-deprived. Speculatively, hungry overweight/obese individuals also appear to use cognitive strategies to reduce a maintained attentional bias for food stimuli, perhaps in an attempt to prevent disinhibited food intake. However, in order to draw firm conclusions, replication studies are needed. Copyright 2009 Elsevier Ltd. All rights reserved.

The relationship of Chlamydophila pneumoniae with schizophrenia: The role of brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) in this relationship.

PubMed

Kalayci, Fatma; Ozdemir, Armagan; Saribas, Suat; Yuksel, Pelin; Ergin, Sevgi; Kuskucu, Ali Mert; Poyraz, Cana Aksoy; Balcioglu, Ibrahim; Alpay, Nihat; Kurt, Aykut; Sezgin, Zeynep; Kocak, Banu Tufan; Icel, Rana Sucu; Can, Gunay; Tokman, Hrisi Bahar; Kocazeybek, Bekir

Several pathogens have been suspected of playing a role in the pathogenesis of schizophrenia. Chronic inflammation has been proposed to occur as a result of persistent infection caused by Chlamydophila pneumoniae cells that reside in brain endothelial cells for many years. It was recently hypothesized that brain-derived neurotrophic factor (BDNF) and neurotrophin-3 (NT-3) may play prominent roles in the development of schizophrenia. NT-3 and BDNF levels have been suggested to change in response to various manifestations of infection. Therefore, we aimed to elucidate the roles of BDNF and NT3 in the schizophrenia-C. pneumoniae infection relationship. RT-PCR, immunofluorescence and ELISA methods were used. Fifty patients suffering from schizophrenia and 35 healthy individuals were included as the patient group (PG) and the healthy control group (HCG), respectively. We detected persistent infection in 14 of the 50 individuals in the PG and in 1 of the 35 individuals in the HCG. A significant difference was found between the two groups (p<0.05). Twenty-two individuals in the PG and 13 in the HCG showed seropositivity for past C. pneumoniae infection, and no difference was observed between the groups (p>0.05). C. pneumoniae DNA was not detected in any group. A significant difference in NT-3 levels was observed between the groups, with very low levels in the PG (p<0.001). A significant difference in BDNF levels was also found, with lower levels in the PG (p<0.05). The mean serum NT-3 level was higher in the PG cases with C. pneumoniae seropositivity than in seronegative cases; however, this difference was not statistically significant (p>0.05). In conclusion, we suggest that NT-3 levels during persistent C. pneumoniae infection may play a role in this relationship. Copyright © 2016 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

Cumulative effects of anti-androgenic chemical mixtures and ...

EPA Pesticide Factsheets

Kembra L. Howdeshell and L. Earl Gray, Jr.Toxicological studies of defined chemical mixtures assist human health risk assessment by characterizing the joint action of chemicals. This presentation will review the effects of anti-androgenic chemical mixtures on reproductive tract development in rats with a special focus on the reproductive toxicant phthalates. Observed mixture data are compared to mathematical mixture model predictions to determine how the individual chemicals in a mixture interact (e.g., response addition – probabilities of response for each individual chemical are added; dose-addition – the doses of each individual chemical at a given mixture dose are combined together based on the relative potency of the individual chemicals). Phthalate mixtures are observed to act in a dose-additive manner based on the relative potency of the individual phthalates to suppress fetal testosterone production. Similar dose-additive effects have been reported for mixtures of phthalates with anti-androgenic pesticides of differing mechanisms. Data from these phthalate experiments in rats can be used in conjunction with human biomonitoring data to determine individual hazard ratios. Furthermore, data from the toxicological studies can inform the analysis of human biomonitoring data on the association of detected chemicals and their metabolites with measured health outcomes. Data from phthalate experiments in rats can be used in conjunction with human biomonit

The Memory Cytotoxic T-Lymphocyte (CTL) Response to Human Cytomegalovirus Infection Contains Individual Peptide-Specific CTL Clones That Have Undergone Extensive Expansion In Vivo

PubMed Central

Weekes, Michael P.; Wills, Mark R.; Mynard, Kim; Carmichael, Andrew J.; Sissons, J. G. Patrick

1999-01-01

Human cytomegalovirus (HCMV)-specific CD8+ cytotoxic T lymphocytes (CTL) appear to play an important role in the control of virus replication and in protection against HCMV-related disease. We have previously reported high frequencies of memory CTL precursors (CTLp) specific to the HCMV tegument protein pp65 in the peripheral blood of healthy virus carriers. In some individuals, the CTL response to this protein is focused on only a single epitope, whereas in other virus carriers CTL recognized multiple epitopes which we identified by using synthetic peptides. We have analyzed the clonal composition of the memory CTL response to four of these pp65 epitopes by sequencing the T-cell receptors (TCR) of multiple independently derived epitope-specific CTL clones, which were derived by formal single-cell cloning or from clonal CTL microcultures. In all cases, we have observed a high degree of clonal focusing: the majority of CTL clones specific to a defined pp65 peptide from any one virus carrier use only one or two different TCRs at the level of the nucleotide sequence. Among virus carriers who have the same major histocompatibility complex (MHC) class I allele, we observed that CTL from different donors that recognize the same peptide-MHC complex often used the same Vβ segment, although other TCR gene segments and CDR3 length were not in general conserved. We have also examined the clonal composition of CTL specific to pp65 peptides in asymptomatic human immunodeficiency virus-infected individuals. We have observed a similarly focused peptide-specific CTL response. Thus, the large population of circulating HCMV peptide-specific memory CTLp in virus carriers in fact contains individual CTL clones that have undergone extensive clonal expansion in vivo. PMID:9971792

Comparing Motor Skills in Autism Spectrum Individuals With and Without Speech Delay

PubMed Central

Barbeau, Elise B.; Meilleur, Andrée‐Anne S.; Zeffiro, Thomas A.

2015-01-01

Movement atypicalities in speed, coordination, posture, and gait have been observed across the autism spectrum (AS) and atypicalities in coordination are more commonly observed in AS individuals without delayed speech (DSM‐IV Asperger) than in those with atypical or delayed speech onset. However, few studies have provided quantitative data to support these mostly clinical observations. Here, we compared perceptual and motor performance between 30 typically developing and AS individuals (21 with speech delay and 18 without speech delay) to examine the associations between limb movement control and atypical speech development. Groups were matched for age, intelligence, and sex. The experimental design included: an inspection time task, which measures visual processing speed; the Purdue Pegboard, which measures finger dexterity, bimanual performance, and hand‐eye coordination; the Annett Peg Moving Task, which measures unimanual goal‐directed arm movement; and a simple reaction time task. We used analysis of covariance to investigate group differences in task performance and linear regression models to explore potential associations between intelligence, language skills, simple reaction time, and visually guided movement performance. AS participants without speech delay performed slower than typical participants in the Purdue Pegboard subtests. AS participants without speech delay showed poorer bimanual coordination than those with speech delay. Visual processing speed was slightly faster in both AS groups than in the typical group. Altogether, these results suggest that AS individuals with and without speech delay differ in visually guided and visually triggered behavior and show that early language skills are associated with slower movement in simple and complex motor tasks. Autism Res 2015, 8: 682–693. © 2015 The Authors Autism Research published by Wiley Periodicals, Inc. on behalf of International Society for Autism Research PMID:25820662

The impact of demographic, health-related and social factors on dental services utilization: Systematic review and meta-analysis.

PubMed

Reda, Seif Magdy; Krois, Joachim; Reda, Sophie Franziska; Thomson, William Murray; Schwendicke, Falk

2018-04-16

Regular and/or preventive dental services utilization is an indicator of healthcare access and associated with improved health outcomes. We assessed the proportion of individuals regularly/preventively utilizing dental services, and how this was affected by demographic, health-related and social factors. Three electronic databases (Medline, Embase, Central) were searched (2005-2017). We included observational studies investigating the association between preventive/regular dental service utilization and age, oral and general health, edentulism, family structure and health literacy. The proportion of individuals with regular/preventive utilization overall and in different sub-groups were extracted. Random-effects meta-analyses, with subgroup analyses by region, were performed. Meta-regression was used to assess whether and how associations changed with time and countries' human developmental status (HDI). 103 studies on 7,395,697 participants from 28 countries were included. The global mean (95% CI) proportion of individuals regularly/preventively utilizing dental services was 54% (50-59%). In countries with higher HDI, more individuals regularly/preventively utilized services (p < 0.001). Age did not have a significant impact on utilization in adults (OR = 1.00; 0.89-1.12). Utilization was significantly lower in younger than older children (OR = 0.52; 0.46-0.59), individuals with poorer general health (OR = 0.73; 0.65-0.80) and poorer oral health (OR = 0.64; 0.52-0.75), edentulous individuals (OR = 0.32; 0.23-0.41), and individuals with less supportive family structures (OR = 0.81; 0.73-0.89) or poor health literacy (OR = 0.41; 0.01-0.81). The observed differences within populations did not significantly change with time and were universally present. Regular/preventive utilization varied widely between and within countries. Understanding and tackling the reasons underlying this may help to consistently improve utilization. Higher developmental status of countries is reflected in greater regular/preventive utilization of dental services. However, large demographic, health-related and social differences in utilization remain. These may contribute to dental health inequalities. Copyright © 2018 Elsevier Ltd. All rights reserved.

Individual and social learning processes involved in the acquisition and generalization of tool use in macaques

PubMed Central

Macellini, S.; Maranesi, M.; Bonini, L.; Simone, L.; Rozzi, S.; Ferrari, P. F.; Fogassi, L.

2012-01-01

Macaques can efficiently use several tools, but their capacity to discriminate the relevant physical features of a tool and the social factors contributing to their acquisition are still poorly explored. In a series of studies, we investigated macaques' ability to generalize the use of a stick as a tool to new objects having different physical features (study 1), or to new contexts, requiring them to adapt the previously learned motor strategy (study 2). We then assessed whether the observation of a skilled model might facilitate tool-use learning by naive observer monkeys (study 3). Results of study 1 and study 2 showed that monkeys trained to use a tool generalize this ability to tools of different shape and length, and learn to adapt their motor strategy to a new task. Study 3 demonstrated that observing a skilled model increases the observers' manipulations of a stick, thus facilitating the individual discovery of the relevant properties of this object as a tool. These findings support the view that in macaques, the motor system can be modified through tool use and that it has a limited capacity to adjust the learnt motor skills to a new context. Social factors, although important to facilitate the interaction with tools, are not crucial for tool-use learning. PMID:22106424

I feel good! Gender differences and reporting heterogeneity in self-assessed health.

PubMed

Schneider, Udo; Pfarr, Christian; Schneider, Brit S; Ulrich, Volker

2012-06-01

For empirical analysis and policy-oriented recommendations, the precise measurement of individual health or well-being is essential. The difficulty is that the answer may depend on individual reporting behaviour. Moreover, if an individual's health perception varies with certain attitudes of the respondent, reporting heterogeneity may lead to index or cut-point shifts of the health distribution, causing estimation problems. An index shift is a parallel shift in the thresholds of the underlying distribution of health categories. In contrast, a cut-point shift means that the relative position of the thresholds changes, implying different response behaviour. Our paper aims to detect how socioeconomic determinants and health experiences influence the individual valuation of health. We analyse the reporting behaviour of individuals on their self-assessed health status, a five-point categorical variable. Using German panel data, we control for observed heterogeneity in the categorical health variable as well as unobserved individual heterogeneity in the panel estimation. In the empirical analysis, we find strong evidence for cut-point shifts. Our estimation results show different impacts of socioeconomic and health-related variables on the five categories of self-assessed health. Moreover, the answering behaviour varies between female and male respondents, pointing to gender-specific perception and assessment of health. Hence, in case of reporting heterogeneity, using self-assessed measures in empirical studies may be misleading and the information needs to be handled with care.

Risk and Resilience Factors in Coping with Daily Stress in Adulthood: The Role of Age, Self-Concept Incoherence, and Personal Control

PubMed Central

Diehl, Manfred; Hay, Elizabeth L.

2010-01-01

This study observed young, middle-aged and older adults (N = 239; Mage = 49.6 years, range = 18-89 years) for 30 consecutive days to examine the association between daily stress and negative affect taking into account potential risk (i.e., self-concept incoherence) and resilience factors (i.e., age, perceived personal control). Results indicated that younger individuals and individuals with a more incoherent self-concept showed higher average negative affect across the study. As well, individuals reported higher negative affect on days that they experienced more stress than usual and on days that they reported less control than usual. These main effects were qualified by significant interactions. In particular, the association between daily stress and negative affect was stronger on days on which adults reported low control compared to days on which they reported high control (i.e., perceptions of control buffered stress). Reactivity to daily stress did not differ for individuals of different ages or for individuals with different levels of self-concept incoherence. Although all individuals reported higher negative affect on days on which they reported less control than usual, this association was more pronounced among younger adults. This study helps to elucidate the role of risk and resilience factors when adults are faced with daily stress. PMID:20822228

Gender, level of participation, and type of sport: differences in achievement goal orientation and attributional style.

PubMed

Hanrahan, Stephanie J; Cerin, Ester

2009-07-01

Findings regarding gender differences in achievement goal orientations and attributional style have been somewhat inconsistent. One possible explanation for varied findings is that potentially confounding variables such as level of participation and type of sport have not been considered. Athletes (108 males and 164 females) from team and individual sports, competing at recreational and competitive levels, completed the Task and Ego Orientation in Sport Questionnaire, the Sport Attributional Style Scale, and a demographic questionnaire. Athletes competing in individual sports had a higher ego orientation than those from team sports, and females scored higher in task orientation than males. Individual sport athletes made more internal, stable, and global, and less externally controllable attributions for positive events, and more internal attributions for negative events than team sport athletes. Competitive female athletes made less global attributions for positive events than did recreational female athletes. This difference was not observed in male athletes. Competitive individual, but not team, athletes made less global attributions than recreational individual athletes. The significant interactions regarding globality suggest that the tradition in sport psychology attribution research to focus solely on internality, stability, and controllability may be inadequate. From an applied perspective, sport psychologists and coaches may find it beneficial to target individual sport athletes and males for interventions designed to enhance task orientation. Similarly, team sport athletes may be appropriate as a focus for attribution retraining programs.

Behavioural Type Affects Space Use in a Wild Population of Crows (Corvus corone).

PubMed

Deventer, Sarah A; Uhl, Florian; Bugnyar, Thomas; Miller, Rachael; Fitch, W Tecumseh; Schiestl, Martina; Ringler, Max; Schwab, Christine

2016-11-01

While personality-dependent dispersal is well studied, local space use has received surprisingly little attention in this context, despite the multiple consequences on survival and fitness. Regarding the coping style of individuals, recent studies on personality-dependent space use within a habitat indicate that 'proactive' individuals are wider ranging than 'reactive' ones. However, such studies are still scarce and cover limited taxonomic diversity, and thus, more research is needed to explore whether this pattern generalises across species. We examined the link between coping style and space use in a population of crows ( Corvus corone ) freely inhabiting the urban zoo of Vienna, Austria. We used a binary docility rating (struggle during handling vs. no struggle) and a tonic immobility test to quantify individual coping style. Individual space use was quantified as the number of different sites at which each crow was observed, and we controlled for different number of sightings per individual by creating a space use index. Only the binary docility rating showed repeatability over time, and significantly predicted space use. In contrast to previous studies, we found that reactive crows (no struggle during handling) showed wider ranging space use within the study site than proactive individuals (who struggled during handling). The discrepancy from previous results suggests that the relationship between behavioural type and space use may vary between species, potentially reflecting differences in socioecology.

Analysis of umbu (Spondias tuberosa Arruda (Anacardiaceae)) in different landscape management regimes: a process of incipient domestication?

PubMed

Lins Neto, Ernani Machado de Freitas; Peroni, Nivaldo; Maranhão, Christine Maria Carneiro; Maciel, Maria Inês Sucupira; de Albuquerque, Ulysses Paulino

2012-07-01

Plant domestication is an evolutionary process guided by human groups who modify the landscape for their needs. The objective of this study was to evaluate the phenotypic variations between populations of Spondias tuberosa Arruda (umbuzeiro) when subjected to different local landscape management strategies. The influence of the landscape management system on these populations was evaluated in five identified regional units (mountains, base of mountains, pastures, cultivated areas and home gardens). Ten individuals were randomly selected from each region and subjected to morphological and chemical fruit analysis. The diversity index, based on Simpson's index, was determined for the different populations. We then evaluated the morphological differences between the individual fruits from the distinct landscape areas. We observed no significant differences in morphological diversity between the areas studied. Our data suggest that the umbuzeiro specimens in this region may be in the process of incipient domestication.

Gender differences and pain medication.

PubMed

Richardson, Jen; Holdcroft, Anita

2009-01-01

Subtle genetic and psychological variations are increasingly recognized to contribute to pain and analgesic efficacy and safety. The influence of sex on this relationship remains poorly understood, particularly in humans. The issue is complicated by the overlay of gender onto physical sex, and its associated stereotypes and expectations. Women appear to use more pain-relieving medications than men; however, it remains unclear whether these observations represent true differences in analgesic usage patterns, or reporting bias. Differences in analgesic efficacy relating to body composition, metabolism and hormonal profiles have been demonstrated. Psychological and social elements of gender have also been associated with altered pain experiences and analgesic use profiles, albeit with significant individual variations. Intra-group differences may ultimately prove more important than sex differences. Further research may unravel the various threads linking gender and sex effects on analgesia with the aim of individualizing analgesia to optimize pain relief.

Emotional prosody processing in autism spectrum disorder

PubMed Central

Kliemann, Dorit; Dziobek, Isabel; Heekeren, Hauke R.

2017-01-01

Abstract Individuals with Autism Spectrum Disorder (ASD) are characterized by severe deficits in social communication, whereby the nature of their impairments in emotional prosody processing have yet to be specified. Here, we investigated emotional prosody processing in individuals with ASD and controls with novel, lifelike behavioral and neuroimaging paradigms. Compared to controls, individuals with ASD showed reduced emotional prosody recognition accuracy on a behavioral task. On the neural level, individuals with ASD displayed reduced activity of the STS, insula and amygdala for complex vs basic emotions compared to controls. Moreover, the coupling between the STS and amygdala for complex vs basic emotions was reduced in the ASD group. Finally, groups differed with respect to the relationship between brain activity and behavioral performance. Brain activity during emotional prosody processing was more strongly related to prosody recognition accuracy in ASD participants. In contrast, the coupling between STS and anterior cingulate cortex (ACC) activity predicted behavioral task performance more strongly in the control group. These results provide evidence for aberrant emotional prosody processing of individuals with ASD. They suggest that the differences in the relationship between the neural and behavioral level of individuals with ASD may account for their observed deficits in social communication. PMID:27531389

Mismatch or cumulative stress: toward an integrated hypothesis of programming effects.

PubMed

Nederhof, Esther; Schmidt, Mathias V

2012-07-16

This paper integrates the cumulative stress hypothesis with the mismatch hypothesis, taking into account individual differences in sensitivity to programming. According to the cumulative stress hypothesis, individuals are more likely to suffer from disease as adversity accumulates. According to the mismatch hypothesis, individuals are more likely to suffer from disease if a mismatch occurs between the early programming environment and the later adult environment. These seemingly contradicting hypotheses are integrated into a new model proposing that the cumulative stress hypothesis applies to individuals who were not or only to a small extent programmed by their early environment, while the mismatch hypothesis applies to individuals who experienced strong programming effects. Evidence for the main effects of adversity as well as evidence for the interaction between adversity in early and later life is presented from human observational studies and animal models. Next, convincing evidence for individual differences in sensitivity to programming is presented. We extensively discuss how our integrated model can be tested empirically in animal models and human studies, inviting researchers to test this model. Furthermore, this integrated model should tempt clinicians and other intervenors to interpret symptoms as possible adaptations from an evolutionary biology perspective. Copyright © 2011 Elsevier Inc. All rights reserved.

Small within-day increases in temperature affects boldness and alters personality in coral reef fish.

PubMed

Biro, Peter A; Beckmann, Christa; Stamps, Judy A

2010-01-07

Consistent individual differences in behaviour, termed personality, are common in animal populations and can constrain their responses to ecological and environmental variation, such as temperature. Here, we show for the first time that normal within-daytime fluctuations in temperature of less than 3 degrees C have large effects on personality for two species of juvenile coral reef fish in both observational and manipulative experiments. On average, individual scores on three personality traits (PTs), activity, boldness and aggressiveness, increased from 2.5- to sixfold as a function of temperature. However, whereas most individuals became more active, aggressive and bold across temperature contexts (were plastic), others did not; this changed the individual rank order across temperatures and thus altered personality. In addition, correlations between PTs were consistent across temperature contexts, e.g. fish that were active at a given temperature also tended to be both bold and aggressive. These results (i) highlight the importance of very carefully controlling for temperature when studying behavioural variation among and within individuals and (ii) suggest that individual differences in energy metabolism may contribute to animal personality, given that temperature has large direct effects on metabolic rates in ectotherms.

From Perception to Metacognition: Auditory and Olfactory Functions in Early Blind, Late Blind, and Sighted Individuals

PubMed Central

Cornell Kärnekull, Stina; Arshamian, Artin; Nilsson, Mats E.; Larsson, Maria

2016-01-01

Although evidence is mixed, studies have shown that blind individuals perform better than sighted at specific auditory, tactile, and chemosensory tasks. However, few studies have assessed blind and sighted individuals across different sensory modalities in the same study. We tested early blind (n = 15), late blind (n = 15), and sighted (n = 30) participants with analogous olfactory and auditory tests in absolute threshold, discrimination, identification, episodic recognition, and metacognitive ability. Although the multivariate analysis of variance (MANOVA) showed no overall effect of blindness and no interaction with modality, follow-up between-group contrasts indicated a blind-over-sighted advantage in auditory episodic recognition, that was most pronounced in early blind individuals. In contrast to the auditory modality, there was no empirical support for compensatory effects in any of the olfactory tasks. There was no conclusive evidence for group differences in metacognitive ability to predict episodic recognition performance. Taken together, the results showed no evidence of an overall superior performance in blind relative sighted individuals across olfactory and auditory functions, although early blind individuals exceled in episodic auditory recognition memory. This observation may be related to an experience-induced increase in auditory attentional capacity. PMID:27729884

Stability of Hand Force Production: II. Ascending and Descending Synergies.

PubMed

Reschechtko, Sasha; Latash, Mark L

2018-06-06

We combined the theory of neural control of movement with referent coordinates and the uncontrolled manifold hypothesis to investigate multi-finger coordination. We tested hypotheses related to stabilization of performance by co-varying control variables, translated into apparent stiffness and referent coordinate, at different levels of an assumed hierarchy of control. Subjects produced an accurate combination of total force and total moment of force with the four fingers under visual feedback on both variables and after feedback was partly or completely removed. The "inverse piano" device was used to estimate control variables. We observed strong synergies in the space of hypothetical control variables which stabilized total force and moment of force, as well as weaker synergies stabilizing individual finger forces; while the former were attenuated by alteration of visual feedback, the latter were much less affected. In addition, we investigated the organization of "ascending synergies" stabilizing task-level control variables by co-varied adjustments of finger-level control variables. We observed inter-trial co-variation of individual fingers' referent coordinates stabilizing hand-level referent coordinate, but observed no such co-variation for apparent stiffness. The observations suggest the existence of both descending and ascending synergies in a hierarchical control system. They confirm a trade-off between synergies at different levels of control and corroborate the hypothesis on specialization of different fingers for the control of force and moment. The results provide strong evidence for the importance of central back-coupling loops in ensuring stability of action.

Experience with Malleable Objects Influences Shape-based Object Individuation by Infants

PubMed Central

Woods, Rebecca J.; Schuler, Jena

2014-01-01

Infants’ ability to accurately represent and later recognize previously viewed objects, and conversely, to discriminate novel objects from those previously seen improves remarkably over the first two years of life. During this time, infants acquire extensive experience viewing and manipulating objects and these experiences influence their physical reasoning. Here we posited that infants’ observations of object feature stability (rigid versus malleable) can influence use of those features to individuate two successively viewed objects. We showed 8.5-month-olds a series of objects that could or could not change shape then assessed their use of shape as a basis for object individuation. Infants who explored rigid objects later used shape differences to individuate objects; however, infants who explored malleable objects did not. This outcome suggests that the latter infants did not take into account shape differences during the physical reasoning task and provides further evidence that infants’ attention to object features can be readily modified based on recent experiences. PMID:24561541

Social Phenotypes of Autism Spectrum Disorders and Williams Syndrome: Similarities and Differences

PubMed Central

Asada, Kosuke; Itakura, Shoji

2012-01-01

Autism spectrum disorders (ASD) and Williams syndrome (WS) both are neurodevelopmental disorders, each with a unique social phenotypic pattern. This review article aims to define the similarities and differences between the social phenotypes of ASD and WS. We review studies that have examined individuals with WS using diagnostic assessments such as the Autism Diagnostic Observation Schedule (ADOS), cross-syndrome direct comparison studies, and studies that have individually examined either disorder. We conclude that (1) individuals with these disorders show quite contrasting phenotypes for face processing (i.e., preference to faces and eyes) and sociability (i.e., interest in and motivation to interact with others), and (2) although the ADOS and a direct comparison study on pragmatic language ability suggest more deficits in ASD, individuals with WS are similarly impaired on social cognition and communicative skills. In light of these results, we discuss how cross-syndrome comparisons between ASD and WS can contribute to developmental theory, cognitive neuroscience, and the development and choice of clinical treatments. PMID:22866045

Attentional bias in high math-anxious individuals: evidence from an emotional Stroop task

PubMed Central

Suárez-Pellicioni, Macarena; Núñez-Peña, Maria Isabel; Colomé, Àngels

2015-01-01

Attentional bias toward threatening or emotional information is considered a cognitive marker of anxiety, and it has been described in various clinical and subclinical populations. This study used an emotional Stroop task to investigate whether math anxiety is characterized by an attentional bias toward math-related words. Two previous studies failed to observe such an effect in math-anxious individuals, although the authors acknowledged certain methodological limitations that the present study seeks to avoid. Twenty high math-anxious (HMA) and 20 low math-anxious (LMA) individuals were presented with an emotional Stroop task including math-related and neutral words. Participants in the two groups did not differ in trait anxiety or depression. We found that the HMA group showed slower response times to math-related words than to neutral words, as well as a greater attentional bias (math-related – neutral difference score) than the LMA one, which constitutes the first demonstration of an attentional bias toward math-related words in HMA individuals. PMID:26539137

Constraints on decision making: implications from genetics, personality, and addiction.

PubMed

Baker, Travis E; Stockwell, Tim; Holroyd, Clay B

2013-09-01

An influential neurocomputational theory of the biological mechanisms of decision making, the "basal ganglia go/no-go model," holds that individual variability in decision making is determined by differences in the makeup of a striatal system for approach and avoidance learning. The model has been tested empirically with the probabilistic selection task (PST), which determines whether individuals learn better from positive or negative feedback. In accordance with the model, in the present study we examined whether an individual's ability to learn from positive and negative reinforcement can be predicted by genetic factors related to the midbrain dopamine system. We also asked whether psychiatric and personality factors related to substance dependence and dopamine affect PST performance. Although we found characteristics that predicted individual differences in approach versus avoidance learning, these observations were qualified by additional findings that appear inconsistent with the predictions of the go/no-go model. These results highlight a need for future research to validate the PST as a measure of basal ganglia reward learning.

Active Brownian Particles. From Individual to Collective Stochastic Dynamics

NASA Astrophysics Data System (ADS)

Romanczuk, P.; Bär, M.; Ebeling, W.; Lindner, B.; Schimansky-Geier, L.

2012-03-01

We review theoretical models of individual motility as well as collective dynamics and pattern formation of active particles. We focus on simple models of active dynamics with a particular emphasis on nonlinear and stochastic dynamics of such self-propelled entities in the framework of statistical mechanics. Examples of such active units in complex physico-chemical and biological systems are chemically powered nano-rods, localized patterns in reaction-diffusion system, motile cells or macroscopic animals. Based on the description of individual motion of point-like active particles by stochastic differential equations, we discuss different velocity-dependent friction functions, the impact of various types of fluctuations and calculate characteristic observables such as stationary velocity distributions or diffusion coefficients. Finally, we consider not only the free and confined individual active dynamics but also different types of interaction between active particles. The resulting collective dynamical behavior of large assemblies and aggregates of active units is discussed and an overview over some recent results on spatiotemporal pattern formation in such systems is given.

Alterations in the gut microbiota associated with HIV-1 infection.

PubMed

Lozupone, Catherine A; Li, Marcella; Campbell, Thomas B; Flores, Sonia C; Linderman, Derek; Gebert, Matthew J; Knight, Rob; Fontenot, Andrew P; Palmer, Brent E

2013-09-11

Understanding gut microbiota alterations associated with HIV infection and factors that drive these alterations may help explain gut-linked diseases prevalent with HIV. 16S rRNA sequencing of feces from HIV-infected individuals revealed that HIV infection is associated with highly characteristic gut community changes, and antiretroviral therapy does not consistently restore the microbiota to an HIV-negative state. Despite the chronic gut inflammation characteristic of HIV infection, the associated microbiota showed limited similarity with other inflammatory states and instead showed increased, rather than decreased, diversity. Meta-analysis revealed that the microbiota of HIV-infected individuals in the U.S. was most similar to a Prevotella-rich community composition typically observed in healthy individuals in agrarian cultures of Malawi and Venezuela and related to that of U.S. individuals with carbohydrate-rich, protein- and fat-poor diets. By evaluating innate and adaptive immune responses to lysates from bacteria that differ with HIV, we explore the functional drivers of these compositional differences. Copyright © 2013 Elsevier Inc. All rights reserved.

Changes of glucose utilization by erythrocytes, lactic acid concentration in the serum and blood cells, and haematocrit value during one hour rest after maximal effort in individuals differing in physical efficiency.

PubMed

Tomasik, M

1982-01-01

Glucose utilization by the erythrocytes, lactic acid concentration in the blood and erythrocytes, and haematocrit value were determined before exercise and during one hour rest following maximal exercise in 97 individuals of either sex differing in physical efficiency. In the investigations reported by the author individuals with strikingly high physical fitness performed maximal work one-third greater than that performed by individuals with medium fitness. The serum concentration of lactic acid was in all individuals above the resting value still after 60 minutes of rest. On the other hand, this concentration returned to the normal level in the erythrocytes but only in individuals with strikingly high efficiency. Glucose utilization by the erythrocytes during the restitution period was highest immediately after the exercise in all studied individuals and showed a tendency for more rapid return to resting values again in individuals with highest efficiency. The investigation of very efficient individuals repeated twice demonstrated greater utilization of glucose by the erythrocytes at the time of greater maximal exercise. This was associated with greater lactic acid concentration in the serum and erythrocytes throughout the whole one-hour rest period. The observed facts suggest an active participation of erythrocytes in the process of adaptation of the organism to exercise.

Postoperative Changes in In Vivo Measured Friction in Total Hip Joint Prosthesis during Walking

PubMed Central

Damm, Philipp; Bender, Alwina; Bergmann, Georg

2015-01-01

Loosening of the artificial cup and inlay is the most common reasons for total hip replacement failures. Polyethylene wear and aseptic loosening are frequent reasons. Furthermore, over the past few decades, the population of patients receiving total hip replacements has become younger and more active. Hence, a higher level of activity may include an increased risk of implant loosening as a result of friction-induced wear. In this study, an instrumented hip implant was used to measure the contact forces and friction moments in vivo during walking. Subsequently, the three-dimensional coefficient of friction in vivo was calculated over the whole gait cycle. Measurements were collected from ten subjects at several time points between three and twelve months postoperative. No significant change in the average resultant contact force was observed between three and twelve months postoperative. In contrast, a significant decrease of up to 47% was observed in the friction moment. The coefficient of friction also decreased over postoperative time on average. These changes may be caused by ‘running-in’ effects of the gliding components or by the improved lubricating properties of the synovia. Because the walking velocity and contact forces were found to be nearly constant during the observed period, the decrease in friction moment suggests an increase in fluid viscosity. The peak values of the contact force individually varied by 32%-44%. The friction moment individually differed much more, by 110%-129% at three and up to 451% at twelve months postoperative. The maximum coefficient of friction showed the highest individual variability, about 100% at three and up to 914% at twelve months after surgery. These individual variations in the friction parameters were most likely due to different ‘running-in’ effects that were influenced by the individual activity levels and synovia properties. PMID:25806805

Seeing People, Seeing Things: Individual Differences in Selective Attention.

PubMed

McIntyre, Miranda M; Graziano, William G

2016-09-01

Individuals differ in how they deploy attention to their physical and social environments. These differences have been recognized in various forms as orientations, interests, and preferences, but empirical work examining these differences at a cognitive level is scarce. To address this gap, we conducted two studies to explore the links among attentional processes and interests in people and things. The first study measured selective visual attention toward person- and thing-related image content. In the second study, participants were randomly assigned to describe visually presented scenes using either an observational or narrative story format. Linguistic analyses were conducted to assess attentional bias toward interest-congruent content. Outcomes from both studies suggest that attention and motivational processes are linked to differential interests in physical and social environments. © 2016 by the Society for Personality and Social Psychology, Inc.

Dietary self-control is related to the speed with which health and taste attributes are processed

PubMed Central

Sullivan, Nicolette; Hutcherson, Cendri; Harris, Alison; Rangel, Antonio

2015-01-01

We propose that self-control failures, and variation across individuals in self-control abilities, are partly due to differences in the speed with which the decision-making circuitry processes basic attributes like taste, versus more abstract attributes such as health. We test these hypotheses by combining a dietary choice task with a novel form of mouse tracking that allows us to pinpoint when different attributes are being integrated into the choice process with millisecond temporal resolution. We find that, on average, taste attributes are processed about 195 ms earlier than health attributes during the choice process. We also find that 13 - 39% of observed individual differences in self-control ability can be explained by differences in the relative speed with which taste and health attributes are processed. PMID:25515527

Dietary self-control is related to the speed with which attributes of healthfulness and tastiness are processed.

PubMed

Sullivan, Nicolette; Hutcherson, Cendri; Harris, Alison; Rangel, Antonio

2015-02-01

We propose that self-control failures, and variation across individuals in self-control abilities, are partly due to differences in the speed with which the decision-making circuitry processes basic attributes, such as tastiness, versus more abstract attributes, such as healthfulness. We tested these hypotheses by combining a dietary-choice task with a novel form of mouse tracking that allowed us to pinpoint when different attributes were being integrated into the choice process with temporal resolution at the millisecond level. We found that, on average, tastiness was processed about 195 ms earlier than healthfulness during the choice process. We also found that 13% to 39% of observed individual differences in self-control ability could be explained by differences in the relative speed with which tastiness and healthfulness were processed. © The Author(s) 2014.

Variation of normal tissue complication probability (NTCP) estimates of radiation-induced hypothyroidism in relation to changes in delineation of the thyroid gland.

PubMed

Rønjom, Marianne F; Brink, Carsten; Lorenzen, Ebbe L; Hegedüs, Laszlo; Johansen, Jørgen

2015-01-01

To examine the variations of risk-estimates of radiation-induced hypothyroidism (HT) from our previously developed normal tissue complication probability (NTCP) model in patients with head and neck squamous cell carcinoma (HNSCC) in relation to variability of delineation of the thyroid gland. In a previous study for development of an NTCP model for HT, the thyroid gland was delineated in 246 treatment plans of patients with HNSCC. Fifty of these plans were randomly chosen for re-delineation for a study of the intra- and inter-observer variability of thyroid volume, Dmean and estimated risk of HT. Bland-Altman plots were used for assessment of the systematic (mean) and random [standard deviation (SD)] variability of the three parameters, and a method for displaying the spatial variation in delineation differences was developed. Intra-observer variability resulted in a mean difference in thyroid volume and Dmean of 0.4 cm(3) (SD ± 1.6) and -0.5 Gy (SD ± 1.0), respectively, and 0.3 cm(3) (SD ± 1.8) and 0.0 Gy (SD ± 1.3) for inter-observer variability. The corresponding mean differences of NTCP values for radiation-induced HT due to intra- and inter-observer variations were insignificantly small, -0.4% (SD ± 6.0) and -0.7% (SD ± 4.8), respectively, but as the SDs show, for some patients the difference in estimated NTCP was large. For the entire study population, the variation in predicted risk of radiation-induced HT in head and neck cancer was small and our NTCP model was robust against observer variations in delineation of the thyroid gland. However, for the individual patient, there may be large differences in estimated risk which calls for precise delineation of the thyroid gland to obtain correct dose and NTCP estimates for optimized treatment planning in the individual patient.

Individual differences in adult foreign language learning: the mediating effect of metalinguistic awareness.

PubMed

Brooks, Patricia J; Kempe, Vera

2013-02-01

In this study, we sought to identify cognitive predictors of individual differences in adult foreign-language learning and to test whether metalinguistic awareness mediated the observed relationships. Using a miniature language-learning paradigm, adults (N = 77) learned Russian vocabulary and grammar (gender agreement and case marking) over six 1-h sessions, completing tasks that encouraged attention to phrases without explicitly teaching grammatical rules. The participants' ability to describe the Russian gender and case-marking patterns mediated the effects of nonverbal intelligence and auditory sequence learning on grammar learning and generalization. Hence, even under implicit-learning conditions, individual differences stemmed from explicit metalinguistic awareness of the underlying grammar, which, in turn, was linked to nonverbal intelligence and auditory sequence learning. Prior knowledge of languages with grammatical gender (predominantly Spanish) predicted learning of gender agreement. Transfer of knowledge of gender from other languages to Russian was not mediated by awareness, which suggests that transfer operates through an implicit process akin to structural priming.

A learning perspective on individual differences in skilled reading: Exploring and exploiting orthographic and semantic discrimination cues.

PubMed

Milin, Petar; Divjak, Dagmar; Baayen, R Harald

2017-11-01

The goal of the present study is to understand the role orthographic and semantic information play in the behavior of skilled readers. Reading latencies from a self-paced sentence reading experiment in which Russian near-synonymous verbs were manipulated appear well-predicted by a combination of bottom-up sublexical letter triplets (trigraphs) and top-down semantic generalizations, modeled using the Naive Discrimination Learner. The results reveal a complex interplay of bottom-up and top-down support from orthography and semantics to the target verbs, whereby activations from orthography only are modulated by individual differences. Using performance on a serial reaction time (SRT) task for a novel operationalization of the mental speed hypothesis, we explain the observed individual differences in reading behavior in terms of the exploration/exploitation hypothesis from reinforcement learning, where initially slower and more variable behavior leads to better performance overall. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Assessing Similarity Among Individual Tumor Size Lesion Dynamics: The CICIL Methodology

PubMed Central

Girard, Pascal; Ioannou, Konstantinos; Klinkhardt, Ute; Munafo, Alain

2018-01-01

Mathematical models of tumor dynamics generally omit information on individual target lesions (iTLs), and consider the most important variable to be the sum of tumor sizes (TS). However, differences in lesion dynamics might be predictive of tumor progression. To exploit this information, we have developed a novel and flexible approach for the non‐parametric analysis of iTLs, which integrates knowledge from signal processing and machine learning. We called this new methodology ClassIfication Clustering of Individual Lesions (CICIL). We used CICIL to assess similarities among the TS dynamics of 3,223 iTLs measured in 1,056 patients with metastatic colorectal cancer treated with cetuximab combined with irinotecan, in two phase II studies. We mainly observed similar dynamics among lesions within the same tumor site classification. In contrast, lesions in anatomic locations with different features showed different dynamics in about 35% of patients. The CICIL methodology has also been implemented in a user‐friendly and efficient Java‐based framework. PMID:29388396

Changes in human gut flora with age: an Indian familial study.

PubMed

Marathe, Nachiket; Shetty, Sudarshan; Lanjekar, Vikram; Ranade, Dilip; Shouche, Yogesh

2012-09-26

The gut micro flora plays vital role in health status of the host. The majority of microbes residing in the gut have a profound influence on human physiology and nutrition. Different human ethnic groups vary in genetic makeup as well as the environmental conditions they live in. The gut flora changes with genetic makeup and environmental factors and hence it is necessary to understand the composition of gut flora of different ethnic groups. Indian population is different in physiology from western population (YY paradox) and thus the gut flora in Indian population is likely to differ from the extensively studied gut flora in western population. In this study we have investigated the gut flora of two Indian families, each with three individuals belonging to successive generations and living under the same roof. Denaturation gradient gel electrophoresis analysis showed age-dependant variation in gut microflora amongst the individuals within a family. Different bacterial genera were dominant in the individual of varying age in clone library analysis. Obligate anaerobes isolated from individuals within a family showed age related differences in isolation pattern, with 27% (6 out of 22) of the isolates being potential novel species based on 16S rRNA gene sequence. In qPCR a consistent decrease in Firmicutes number and increase in Bacteroidetes number with increasing age was observed in our subjects, this pattern of change in Firmicutes / Bacteroidetes ratio with age is different than previously reported in European population. There is change in gut flora with age amongst the individuals within a family. The isolation of high percent of novel bacterial species and the pattern of change in Firmicutes /Bacteroidetes ratio with age suggests that the composition of gut flora in Indian individuals may be different than the western population. Thus, further extensive study is needed to define the gut flora in Indian population.

Animal welfare at the group level: more than the sum of individual welfare?

PubMed

Ohl, F; Putman, R J

2014-03-01

Currently assessment and management of animal welfare are based on the supposition that welfare status is something experienced identically by each individual animal when exposed to the same conditions. However, many authors argue that individual welfare cannot be seen as an 'objective' state, but is based on the animal's own self-perception; such perception might vary significantly between individuals which appear to be exposed to exactly the same challenges. We argue that this has two implications: (1) actual perceived welfare status of individuals in a population may vary over a wide range even under identical environmental conditions; (2) animals that appear to an external observer to be in better or poorer welfare condition may all in fact perceive their own individual status as the same. This would imply that optimum welfare of a social group might be achieved in situations where individual group members differ markedly in apparent welfare status and perceive their own welfare as being optimal under differing circumstances. Welfare phenotypes may also vary along a continuum between self-regarding and other-regarding behaviour; a variety of situations exist where (social) individuals appear to invest in the welfare of other individuals instead of maximising their own welfare; in such a case it is necessary to re-evaluate individual welfare within the context of a social group and recognise that there may be consequences for the welfare of individuals, of decisions made at the group level or by other group members.

Cardiorespiratory response to exercise testing in individuals with Alzheimer’s disease

PubMed Central

Billinger, Sandra A.; Vidoni, Eric D.; Honea, Robyn A.; Burns, Jeffrey M.

2011-01-01

Objective To exercise testing in AD and possible disease-related change over time. Though physical activity and fitness are receiving increased attention as a possible adjunct treatment for Alzheimer’s disease (AD), relatively little work has been done characterizing their physiologic response to exercise Design Retrospective assessment of a 2-year, observational study Setting University medical center Participants 50 nondemented individuals and 31 with AD Interventions None Main Outcome Measures Participants underwent a clinical dementia evaluation and performed an incremental exercise test using a treadmill and the modified Bruce protocol at baseline and at a two year follow-up. We examined oxygen consumption, minute ventilation, heart rate and ventilatory equivalents for oxygen and carbon dioxide at submaximal and peak exercise intensities to determine if the measures were different between groups or over time. Results AD and nondemented participants performed similarly at submaximal effort and both groups showed similar change in exercise response over 2 years. However, nondemented individuals had consistently higher values of oxygen consumption (p≤0.02) and minute ventilation at peak effort at baseline (p=0.003). Conclusions Individuals with AD demonstrate physiologic responses to submaximal exercise effort that are not significantly different than individuals without dementia. However, differences are apparent at the extreme of effort. PMID:22133248

Honesty mediates the relationship between serotonin and reaction to unfairness

PubMed Central

Takahashi, Hidehiko; Takano, Harumasa; Camerer, Colin F.; Ideno, Takashi; Okubo, Shigetaka; Matsui, Hiroshi; Tamari, Yuki; Takemura, Kazuhisa; Arakawa, Ryosuke; Kodaka, Fumitoshi; Yamada, Makiko; Eguchi, Yoko; Murai, Toshiya; Okubo, Yoshiro; Kato, Motoichiro; Ito, Hiroshi; Suhara, Tetsuya

2012-01-01

How does one deal with unfair behaviors? This subject has long been investigated by various disciplines including philosophy, psychology, economics, and biology. However, our reactions to unfairness differ from one individual to another. Experimental economics studies using the ultimatum game (UG), in which players must decide whether to accept or reject fair or unfair offers, have also shown that there are substantial individual differences in reaction to unfairness. However, little is known about psychological as well as neurobiological mechanisms of this observation. We combined a molecular imaging technique, an economics game, and a personality inventory to elucidate the neurobiological mechanism of heterogeneous reactions to unfairness. Contrary to the common belief that aggressive personalities (impulsivity or hostility) are related to the high rejection rate of unfair offers in UG, we found that individuals with apparently peaceful personalities (straightforwardness and trust) rejected more often and were engaged in personally costly forms of retaliation. Furthermore, individuals with a low level of serotonin transporters in the dorsal raphe nucleus (DRN) are honest and trustful, and thus cannot tolerate unfairness, being candid in expressing their frustrations. In other words, higher central serotonin transmission might allow us to behave adroitly and opportunistically, being good at playing games while pursuing self-interest. We provide unique neurobiological evidence to account for individual differences of reaction to unfairness. PMID:22371595

Honesty mediates the relationship between serotonin and reaction to unfairness.

PubMed

Takahashi, Hidehiko; Takano, Harumasa; Camerer, Colin F; Ideno, Takashi; Okubo, Shigetaka; Matsui, Hiroshi; Tamari, Yuki; Takemura, Kazuhisa; Arakawa, Ryosuke; Kodaka, Fumitoshi; Yamada, Makiko; Eguchi, Yoko; Murai, Toshiya; Okubo, Yoshiro; Kato, Motoichiro; Ito, Hiroshi; Suhara, Tetsuya

2012-03-13

How does one deal with unfair behaviors? This subject has long been investigated by various disciplines including philosophy, psychology, economics, and biology. However, our reactions to unfairness differ from one individual to another. Experimental economics studies using the ultimatum game (UG), in which players must decide whether to accept or reject fair or unfair offers, have also shown that there are substantial individual differences in reaction to unfairness. However, little is known about psychological as well as neurobiological mechanisms of this observation. We combined a molecular imaging technique, an economics game, and a personality inventory to elucidate the neurobiological mechanism of heterogeneous reactions to unfairness. Contrary to the common belief that aggressive personalities (impulsivity or hostility) are related to the high rejection rate of unfair offers in UG, we found that individuals with apparently peaceful personalities (straightforwardness and trust) rejected more often and were engaged in personally costly forms of retaliation. Furthermore, individuals with a low level of serotonin transporters in the dorsal raphe nucleus (DRN) are honest and trustful, and thus cannot tolerate unfairness, being candid in expressing their frustrations. In other words, higher central serotonin transmission might allow us to behave adroitly and opportunistically, being good at playing games while pursuing self-interest. We provide unique neurobiological evidence to account for individual differences of reaction to unfairness.

Gender differences in the association between socioeconomic status and subclinical atherosclerosis.

PubMed

Grimaud, Olivier; Lapostolle, Annabelle; Berr, Claudine; Helmer, Catherine; Dufouil, Carole; Kihal, Wahida; Alpérovitch, Annick; Chauvin, Pierre

2013-01-01

This study explored the pattern of associations between socioeconomic status (SES) and atherosclerosis progression (as indicated by carotid intima media thickness, CIMT) across gender. Cross-sectional analysis of a sample of 5474 older persons (mean age 73 years) recruited between 1999 and 2001 in the 3C study (France). We fitted linear regression models including neighborhood SES, individual SES and cardiovascular risk factors. CIMT was on average 24 µm higher in men (95% CI: 17 to 31). Neighborhood SES was inversely associated with CIMT in women only (highest versus lowest tertiles: -12.2 µm, 95%CI -22 to -2.4). This association persisted when individual SES and risk factors were accounted for. High individual education was associated with lower CIMT in men (-21.4 µm 95%CI -37.5 to -5.3) whereas high professional status was linked to lower CIMT among women (-15.7 µm 95%CI: -29.2 to -2.2). Adjustment for cardiovascular risk factors resulted in a slightly more pronounced reduction of the individual SES-CIMT association observed in men than in women. In this sample, neighborhood and individual SES displayed different patterns of associations with subclinical atherosclerosis across gender. This suggests that the causal pathways leading to SES variations in atherosclerosis may differ among men and women.

Advanced Statistical Analyses to Reduce Inconsistency of Bond Strength Data.

PubMed

Minamino, T; Mine, A; Shintani, A; Higashi, M; Kawaguchi-Uemura, A; Kabetani, T; Hagino, R; Imai, D; Tajiri, Y; Matsumoto, M; Yatani, H

2017-11-01

This study was designed to clarify the interrelationship of factors that affect the value of microtensile bond strength (µTBS), focusing on nondestructive testing by which information of the specimens can be stored and quantified. µTBS test specimens were prepared from 10 noncarious human molars. Six factors of µTBS test specimens were evaluated: presence of voids at the interface, X-ray absorption coefficient of resin, X-ray absorption coefficient of dentin, length of dentin part, size of adhesion area, and individual differences of teeth. All specimens were observed nondestructively by optical coherence tomography and micro-computed tomography before µTBS testing. After µTBS testing, the effect of these factors on µTBS data was analyzed by the general linear model, linear mixed effects regression model, and nonlinear regression model with 95% confidence intervals. By the general linear model, a significant difference in individual differences of teeth was observed ( P < 0.001). A significantly positive correlation was shown between µTBS and length of dentin part ( P < 0.001); however, there was no significant nonlinearity ( P = 0.157). Moreover, a significantly negative correlation was observed between µTBS and size of adhesion area ( P = 0.001), with significant nonlinearity ( P = 0.014). No correlation was observed between µTBS and X-ray absorption coefficient of resin ( P = 0.147), and there was no significant nonlinearity ( P = 0.089). Additionally, a significantly positive correlation was observed between µTBS and X-ray absorption coefficient of dentin ( P = 0.022), with significant nonlinearity ( P = 0.036). A significant difference was also observed between the presence and absence of voids by linear mixed effects regression analysis. Our results showed correlations between various parameters of tooth specimens and µTBS data. To evaluate the performance of the adhesive more precisely, the effect of tooth variability and a method to reduce variation in bond strength values should also be considered.

Leisure sports and postural control: can a black belt protect your balance from aging?

PubMed

Krampe, Ralf T; Smolders, Caroline; Doumas, Michail

2014-03-01

To determine potential benefits of intensive leisure sports for age-related changes in postural control, we tested 3 activity groups comprising 70 young (M = 21.67 years, SD = 2.80) and 73 older (M = 62.60 years, SD = 5.19) men. Activity groups were martial artists, who held at least 1st Dan (black belt), sportive individuals exercising sports without explicit balance components, and nonsportive controls. Martial artists had an advantage over sportive individuals in dynamic posture tasks (upright stance on a sway-referenced platform), and these 2 active groups showed better postural control than nonsportive participants. Age-related differences in postural control were larger in nonsportive men compared with the 2 active groups, who were similar in this respect. In contrast, negative age differences in other sensorimotor and cognitive functions did not differ between activity groups. We concluded that individuals engaging in intensive recreational sports have long-term advantages in postural control. However, even in older martial artists with years of practice in their sports, we observed considerable differences favoring the young. (c) 2014 APA, all rights reserved.

Locomotion Strategy and Magnitude of Ground Reaction Forces During Treadmill Training on ISS.

PubMed

Fomina, Elena; Savinkina, Alexandra

2017-09-01

Creation of the cosmonaut in-flight physical training process is currently based on the leading role of support afferents in the development of hypogravity changes in the motor system. We assume that the strength of support afferents is related to the magnitude of the ground reaction forces (GRF). For this purpose it was necessary to compare the GRF magnitude on the Russian BD-2 treadmill for different locomotion types (walking and running), modes (active and passive), and subjects. Relative GRF values were analyzed while subjects performed walking and running during active and passive modes of treadmill belt movement under 1 G (N = 6) and 0 G (N = 4) conditions. For different BD-2 modes and both types of locomotion, maximum GRF values varied in both 0 G and 1 G. Considerable individual variations were also found in the locomotion strategies, as well as in maximum GRF values. In 0 G, the smallest GRF values were observed for walking in active mode, and the largest during running in passive mode. In 1 G, GRF values were higher during running than while walking, but the difference between active and passive modes was not observed; we assume this was due to the uniqueness of the GRF profile. The maximum GRF recorded during walking and running in active and passive modes depended on the individual pattern of locomotion. The maximum GRF values that we recorded on BD-2 were close to values found by other researchers. The observations from this study could guide individualized countermeasures prescriptions for microgravity.Fomina E, Savinkina A. Locomotion strategy and magnitude of ground reaction forces during treadmill training on ISS. Aerosp Med Hum Perform. 2017; 88(9):841-849.

Regional Brain Shrinkage over Two Years: Individual Differences and Effects of Pro-Inflammatory Genetic Polymorphisms

PubMed Central

Persson, N.; Ghisletta, P.; Dahle, C.L.; Bender, A.R.; Yang, Y.; Yuan, P.; Daugherty, A.M.; Raz, N.

2014-01-01

We examined regional changes in brain volume in healthy adults (N = 167, age 19-79 years at baseline; N = 90 at follow-up) over approximately two years. With latent change score models, we evaluated mean change and individual differences in rates of change in 10 anatomically-defined and manually-traced regions of interest (ROIs): lateral prefrontal cortex (LPFC), orbital frontal cortex (OF), prefrontal white matter (PFw), hippocampus (HC), parahippocampal gyrus (PhG), caudate nucleus (Cd), putamen (Pt), insula (In), cerebellar hemispheres (CbH), and primary visual cortex (VC). Significant mean shrinkage was observed in the HC, CbH, In, OF, and the PhG, and individual differences in change were noted in all regions, except the OF. Pro-inflammatory genetic variants mediated shrinkage in PhG and CbH. Carriers of two T alleles of interleukin-1β (IL-1βC-511T, rs16944) and a T allele of methylenetetrahydrofolate reductase (MTHFRC677T, rs1801133) polymorphisms showed increased PhG shrinkage. No effects of a pro-inflammatory polymorphism for C-reactive protein (CRP-286C>A>T, rs3091244) or apolipoprotein (APOE) ε4 allele were noted. These results replicate the pattern of brain shrinkage observed in previous studies, with a notable exception of the LPFC thus casting doubt on the unique importance of prefrontal cortex in aging. Larger baseline volumes of CbH and In were associated with increased shrinkage, in conflict with the brain reserve hypothesis. Contrary to previous reports, we observed no significant linear effects of age and hypertension on regional brain shrinkage. Our findings warrant further investigation of the effects of neuroinflammation on structural brain change throughout the lifespan. PMID:25264227

False Belief Reasoning in Adults with and without Autistic Spectrum Disorder: Similarities and Differences.

PubMed

Sommer, Monika; Döhnel, Katrin; Jarvers, Irina; Blaas, Lore; Singer, Manuela; Nöth, Victoria; Schuwerk, Tobias; Rupprecht, Rainer

2018-01-01

A central diagnostic criteria for autism spectrum disorder (ASD) is the qualitative impairment in reciprocal social interaction and a prominent hypotheses that tried to explain this impairment is the Theory of Mind (ToM) deficit hypotheses. On a behavioral level the critical test for having a ToM, the understanding of false beliefs (FB), is often used for testing ToM abilities in individuals with ASD. Investigating the neural underpinnings several neuroimaging studies revealed a network of areas involved in FB reasoning in neurotypical individuals. For ASD individuals the neural correlates of false belief processing are largely unknown. Using functional magnetic resonance imaging and an adapted unexpected transfer task, that makes it possible to distinguish between the computation of diverging beliefs and the selection of a belief-associated response, we investigated a group of adult high-functioning individuals with ASD ( N = 15) and an age and IQ matched group of neurotypical adults (NT; N = 15). On the behavioral level we found no group differences. On the neural level, results were two-fold: In the story phase, in which participants had to compute whether the character's belief is congruent or incongruent to their own belief, there were no differences between neurotypical participants and those diagnosed with ASD. But, in the subsequent question phase, participants with ASD showed increased activity in the bilateral anterior prefrontal cortex, the left posterior frontal cortex, the left superior temporal gyrus, and the left temporoparietal area. These results suggest that during the story phase in which the participants processed observable actions the neural correlates do not differ between adult individuals with ASD and NT individuals. But in the question phase in which participants had to infer an unobservable mental state results revealed neural differences between the two groups. Possibly, these subtle neural processing differences may contribute to the fact that adult ASD individuals are able to master explicit false belief tasks but fail to apply their strategies during everyday social interaction.

False Belief Reasoning in Adults with and without Autistic Spectrum Disorder: Similarities and Differences

PubMed Central

Sommer, Monika; Döhnel, Katrin; Jarvers, Irina; Blaas, Lore; Singer, Manuela; Nöth, Victoria; Schuwerk, Tobias; Rupprecht, Rainer

2018-01-01

A central diagnostic criteria for autism spectrum disorder (ASD) is the qualitative impairment in reciprocal social interaction and a prominent hypotheses that tried to explain this impairment is the Theory of Mind (ToM) deficit hypotheses. On a behavioral level the critical test for having a ToM, the understanding of false beliefs (FB), is often used for testing ToM abilities in individuals with ASD. Investigating the neural underpinnings several neuroimaging studies revealed a network of areas involved in FB reasoning in neurotypical individuals. For ASD individuals the neural correlates of false belief processing are largely unknown. Using functional magnetic resonance imaging and an adapted unexpected transfer task, that makes it possible to distinguish between the computation of diverging beliefs and the selection of a belief-associated response, we investigated a group of adult high-functioning individuals with ASD (N = 15) and an age and IQ matched group of neurotypical adults (NT; N = 15). On the behavioral level we found no group differences. On the neural level, results were two-fold: In the story phase, in which participants had to compute whether the character's belief is congruent or incongruent to their own belief, there were no differences between neurotypical participants and those diagnosed with ASD. But, in the subsequent question phase, participants with ASD showed increased activity in the bilateral anterior prefrontal cortex, the left posterior frontal cortex, the left superior temporal gyrus, and the left temporoparietal area. These results suggest that during the story phase in which the participants processed observable actions the neural correlates do not differ between adult individuals with ASD and NT individuals. But in the question phase in which participants had to infer an unobservable mental state results revealed neural differences between the two groups. Possibly, these subtle neural processing differences may contribute to the fact that adult ASD individuals are able to master explicit false belief tasks but fail to apply their strategies during everyday social interaction. PMID:29503627

Identification, Characterization, and Mapping of a Novel SNP Associated with Body Color Transparency in Juvenile Red Sea Bream (Pagrus major).

PubMed

Sawayama, Eitaro; Noguchi, Daiki; Nakayama, Kei; Takagi, Motohiro

2018-03-23

We previously reported a body color deformity in juvenile red sea bream, which shows transparency in the juvenile stage because of delayed chromatophore development compared with normal individuals, and this finding suggested a genetic cause based on parentage assessments. To conduct marker-assisted selection to eliminate broodstock inheriting the causative gene, developing DNA markers associated with the phenotype was needed. We first conducted SNP mining based on AFLP analysis using bulked-DNA from normal and transparent individuals. One SNP was identified from a transparent-specific AFLP fragment, which significantly associated with transparent individuals. Two alleles (A/G) were observed in this locus, and the genotype G/G was dominantly observed in the transparent groups (97.1%) collected from several production lots produced from different broodstock populations. A few normal individuals inherited the G/G genotype (5.0%), but the A/A and A/G genotypes were dominantly observed in the normal groups. The homologs region of the SNP was searched using a medaka genome database, and intron 12 of the Nell2a gene (located on chromosome 6 of the medaka genome) was highly matched. We also mapped the red sea bream Nell2a gene on the previously developed linkage maps, and this gene was mapped on a male linkage group, LG4-M. The newly found SNP was useful in eliminating broodstock possessing the causative gene of the body color transparency observed in juvenile stage of red sea bream.

Correlational selection on personality and social plasticity: morphology and social context determine behavioural effects on mating success.

PubMed

Montiglio, Pierre-Olivier; Wey, Tina W; Chang, Ann T; Fogarty, Sean; Sih, Andrew

2017-03-01

Despite a central line of research aimed at quantifying relationships between mating success and sexually dimorphic traits (e.g., ornaments), individual variation in sexually selected traits often explains only a modest portion of the variation in mating success. Another line of research suggests that a significant portion of the variation in mating success observed in animal populations could be explained by correlational selection, where the fitness advantage of a given trait depends on other components of an individual's phenotype and/or its environment. We tested the hypothesis that interactions between multiple traits within an individual (phenotype dependence) or between an individual's phenotype and its social environment (context dependence) can select for individual differences in behaviour (i.e., personality) and social plasticity. To quantify the importance of phenotype- and context-dependent selection on mating success, we repeatedly measured the behaviour, social environment and mating success of about 300 male stream water striders, Aquarius remigis. Rather than explaining individual differences in long-term mating success, we instead quantified how the combination of a male's phenotype interacted with the immediate social context to explain variation in hour-by-hour mating decisions. We suggest that this analysis captures more of the mechanisms leading to differences in mating success. Males differed consistently in activity, aggressiveness and social plasticity. The mating advantage of these behavioural traits depended on male morphology and varied with the number of rival males in the pool, suggesting mechanisms selecting for consistent differences in behaviour and social plasticity. Accounting for phenotype and context dependence improved the amount of variation in male mating success we explained statistically by 30-274%. Our analysis of the determinants of male mating success provides important insights into the evolutionary forces that shape phenotypic variation. In particular, our results suggest that sexual selection is likely to favour individual differences in behaviour, social plasticity (i.e., individuals adjusting their behaviour), niche preference (i.e., individuals dispersing to particular social conditions) or social niche construction (i.e., individuals modifying the social environment). The true effect of sexual traits can only be understood in interaction with the individual's phenotype and environment. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Tocochromanol content and composition in different species of the parasitic flowering plant genus Cuscuta.

PubMed

van der Kooij, Thomas A W; Krupinska, Karin; Krause, Kirsten

2005-07-01

The holoparasitic plant genus Cuscuta is comprised of species with various degrees of plastid functionality and significant differences in photosynthetic capacity, ranging from moderate to no photosynthetic carbon fixation. In the present study, several Cuscuta species were analyzed with respect to the overall contents of tocochromanols and plastoquinone and the levels of the individual tocochromanols. No correlations among photosynthetic capacity, the amount of carotenoids, of plastoquinone and of tocochromanols were observed. On the contrary, wide variation in the composition of the tocochromanol fraction was observed among different species, as well as in stems of the same species in response to starvation conditions. The implications of these findings are discussed.

Interplay of different NOM fouling mechanisms during ultrafiltration for drinking water production.

PubMed

Jermann, D; Pronk, W; Meylan, S; Boller, M

2007-04-01

Ultrafiltration is an emerging technology for drinking water production, but a main challenge remains the lack of understanding about fouling. This paper investigates the impact of molecular interactions between different natural organic matter (NOM) compounds on ultrafiltration fouling mechanisms. We performed dead-end filtration experiments with individual and mixed humic acid and alginate (polysaccharide). Alginate showed detrimental, but mostly reversible, flux decline and high solute retention. Our results indicate that this was caused by pore blocking transformed into cake building and weak molecular foulant-membrane and foulant-foulant interactions. In the presence of calcium, aggravated fouling was observed, related to complexation of alginate and its subsequently induced gel formation. With humic acid, more severe irreversible fouling occurred due to humic acid adsorption. Minor adsorption of alginate onto the membrane was also observed, which probably caused the substantial irreversible flux decline. The fouling characteristics in the mixtures reflected a combination of the individual humic acid and alginate experiments and we conclude, that the individual fouling mechanisms mutually influence each other. A model elucidates this interplay of the individual fouling mechanisms via hydrophobic and electrostatic interactions. In our study such an interplay resulted in an alginate cake, or gel in the presence of calcium, which is relatively irreversibly adsorbed onto the membrane by humic acid associations. This study shows the importance of mutual influences between various foulants for improved understanding of fouling phenomena. Furthermore it shows that substances with a minor individual influence might have a large impact in mixed systems such as natural water.

Reduced Theta-Band Power and Phase Synchrony during Explicit Verbal Memory Tasks in Female, Non-Clinical Individuals with Schizotypal Traits.

PubMed

Choi, Jeong Woo; Jang, Kyoung-Mi; Jung, Ki-Young; Kim, Myung-Sun; Kim, Kyung Hwan

2016-01-01

The study of non-clinical individuals with schizotypal traits has been considered to provide a promising endophenotypic approach to understanding schizophrenia, because schizophrenia is highly heterogeneous, and a number of confounding factors may affect neuropsychological performance. Here, we investigated whether deficits in explicit verbal memory in individuals with schizotypal traits are associated with abnormalities in the local and inter-regional synchrony of brain activity. Memory deficits have been recognized as a core problem in schizophrenia, and previous studies have consistently shown explicit verbal memory impairment in schizophrenic patients. However, the mechanism of this impairment has not been fully revealed. Seventeen individuals with schizotypal traits and 17 age-matched, normal controls participated. Multichannel event-related electroencephalograms (EEGs) were recorded while the subjects performed a continuous recognition task. Event-related spectral perturbations (ERSPs) and inter-regional theta-band phase locking values (TPLVs) were investigated to determine the differences in local and global neural synchrony between the two subject groups. Additionally, the connection patterns of the TPLVs were quantitatively analyzed using graph theory measures. An old/new effect was found in the induced theta-band ERSP in both groups. However, the difference between the old and new was larger in normal controls than in schizotypal trait group. The tendency of elevated old/new effect in normal controls was observed in anterior-posterior theta-band phase synchrony as well. Our results suggest that explicit memory deficits observed in schizophrenia patients can also be found in non-clinical individuals with psychometrically defined schizotypal traits.

Cuticular hydrocarbon phenotypes do not indicate cryptic species in fungus-growing termites (Isoptera: Macrotermitinae).

PubMed

Marten, Andreas; Kaib, Manfred; Brandl, Roland

2009-05-01

In several termite species, distinct differences in the composition of cuticular hydrocarbons among colonies correspond to high genetic divergence of mitochondrial DNA sequences. These observations suggest that hydrocarbon phenotypes represent cryptic species. Different cuticular hydrocarbon phenotypes also are found among colonies of fungus-growing termites of the genus Macrotermes. To determine if these hydrocarbon differences in Macrotermes also indicate cryptic species, we sequenced the mitochondrial CO I gene from species in West and East Africa. Among individuals of a supposed species but belonging to different cuticular hydrocarbon phenotypes, the genetic distances are much smaller than distances between species. Unlike what has been observed in other termites, Macrotermes hydrocarbon phenotypes do not represent cryptic species. Our findings suggest fundamental differences in the evolution and/or function of cuticular hydrocarbons among different termite lineages.

Colorimetry for CRT displays.

PubMed

Golz, Jürgen; MacLeod, Donald I A

2003-05-01

We analyze the sources of error in specifying color in CRT displays. These include errors inherent in the use of the color matching functions of the CIE 1931 standard observer when only colorimetric, not radiometric, calibrations are available. We provide transformation coefficients that prove to correct the deficiencies of this observer very well. We consider four different candidate sets of cone sensitivities. Some of these differ substantially; variation among candidate cone sensitivities exceeds the variation among phosphors. Finally, the effects of the recognized forms of observer variation on the visual responses (cone excitations or cone contrasts) generated by CRT stimuli are investigated and quantitatively specified. Cone pigment polymorphism gives rise to variation of a few per cent in relative excitation by the different phosphors--a variation larger than the errors ensuing from the adoption of the CIE standard observer, though smaller than the differences between some candidate cone sensitivities. Macular pigmentation has a larger influence, affecting mainly responses to the blue phosphor. The estimated combined effect of all sources of observer variation is comparable in magnitude with the largest differences between competing cone sensitivity estimates but is not enough to disrupt very seriously the relation between the L and M cone weights and the isoluminance settings of individual observers. It is also comparable with typical instrumental colorimetric errors, but we discuss these only briefly.

Individual covariation in life-history traits: seeing the trees despite the forest

USGS Publications Warehouse

Cam, E.; Link, W.A.; Cooch, E.G.; Monnat, J.-Y.; Danchin, E.

2002-01-01

We investigated the influence of age on survival and breeding rates in a long-lived species Rissa tridactyla using models with individual random effects permitting variation and covariation in fitness components among individuals. Differences in survival or breeding probabilities among individuals are substantial, and there was positive covariation between survival and breeding probability; birds that were more likely to survive were also more likely to breed, given that they survived. The pattern of age-related variation in these rates detected at the individual level differed from that observed at the population level. Our results provided confirmation of what has been suggested by other investigators: within-cohort phenotypic selection can mask senescence. Although this phenomenon has been extensively studied in humans and captive animals, conclusive evidence of the discrepancy between population-level and individual-level patterns of age-related variation in life-history traits is extremely rare in wild animal populations. Evolutionary studies of the influence of age on life-history traits should use approaches differentiating population level from the genuine influence of age: only the latter is relevant to theories of life-history evolution. The development of models permitting access to individual variation in fitness is a promising advance for the study of senescence and evolutionary processes.

Post-error response inhibition in high math-anxious individuals: Evidence from a multi-digit addition task.

PubMed

Núñez-Peña, M Isabel; Tubau, Elisabet; Suárez-Pellicioni, Macarena

2017-06-01

The aim of the study was to investigate how high math-anxious (HMA) individuals react to errors in an arithmetic task. Twenty HMA and 19 low math-anxious (LMA) individuals were presented with a multi-digit addition verification task and were given response feedback. Post-error adjustment measures (response time and accuracy) were analyzed in order to study differences between groups when faced with errors in an arithmetical task. Results showed that both HMA and LMA individuals were slower to respond following an error than following a correct answer. However, post-error accuracy effects emerged only for the HMA group, showing that they were also less accurate after having committed an error than after giving the right answer. Importantly, these differences were observed only when individuals needed to repeat the same response given in the previous trial. These results suggest that, for HMA individuals, errors caused reactive inhibition of the erroneous response, facilitating performance if the next problem required the alternative response but hampering it if the response was the same. This stronger reaction to errors could be a factor contributing to the difficulties that HMA individuals experience in learning math and doing math tasks. Copyright © 2017 Elsevier B.V. All rights reserved.

Facial Recognition in a Group-Living Cichlid Fish.

PubMed

Kohda, Masanori; Jordan, Lyndon Alexander; Hotta, Takashi; Kosaka, Naoya; Karino, Kenji; Tanaka, Hirokazu; Taniyama, Masami; Takeyama, Tomohiro

2015-01-01

The theoretical underpinnings of the mechanisms of sociality, e.g. territoriality, hierarchy, and reciprocity, are based on assumptions of individual recognition. While behavioural evidence suggests individual recognition is widespread, the cues that animals use to recognise individuals are established in only a handful of systems. Here, we use digital models to demonstrate that facial features are the visual cue used for individual recognition in the social fish Neolamprologus pulcher. Focal fish were exposed to digital images showing four different combinations of familiar and unfamiliar face and body colorations. Focal fish attended to digital models with unfamiliar faces longer and from a further distance to the model than to models with familiar faces. These results strongly suggest that fish can distinguish individuals accurately using facial colour patterns. Our observations also suggest that fish are able to rapidly (≤ 0.5 sec) discriminate between familiar and unfamiliar individuals, a speed of recognition comparable to primates including humans.

The scent of disease: human body odor contains an early chemosensory cue of sickness.

PubMed

Olsson, Mats J; Lundström, Johan N; Kimball, Bruce A; Gordon, Amy R; Karshikoff, Bianka; Hosseini, Nishteman; Sorjonen, Kimmo; Olgart Höglund, Caroline; Solares, Carmen; Soop, Anne; Axelsson, John; Lekander, Mats

2014-03-01

Observational studies have suggested that with time, some diseases result in a characteristic odor emanating from different sources on the body of a sick individual. Evolutionarily, however, it would be more advantageous if the innate immune response were detectable by healthy individuals as a first line of defense against infection by various pathogens, to optimize avoidance of contagion. We activated the innate immune system in healthy individuals by injecting them with endotoxin (lipopolysaccharide). Within just a few hours, endotoxin-exposed individuals had a more aversive body odor relative to when they were exposed to a placebo. Moreover, this effect was statistically mediated by the individuals' level of immune activation. This chemosensory detection of the early innate immune response in humans represents the first experimental evidence that disease smells and supports the notion of a "behavioral immune response" that protects healthy individuals from sick ones by altering patterns of interpersonal contact.

Extra virgin olive oil aroma release after interaction with human saliva from individuals with different body mass index.

PubMed

Genovese, Alessandro; Rispoli, Tiziana; Sacchi, Raffaele

2018-07-01

The interindividual variability observed in saliva characteristics raises the question of its relationship with variability in fat sensory perception, particularly in aroma compounds. In the present study, which aimed to measure aroma release from different individuals, eleven key aroma compounds of extra virgin olive oil (EVOO) were monitored and quantified in dynamic headspace after an in vitro interaction between EVOO and human saliva. Therefore, 60 individuals were studied from those who were normal weight (NW), overweight (OW) and obese (O). OW and O demonstrate a higher release of C 6 compounds compared to NW. By contrast, NW have a higher release of C 5 compounds. Pentanal and hexanal also increased after saliva interaction in a refined olive oil that is free from volatiles. Among the saliva samples with a higher release in NW individuals, only pentanal was different. However, the low levels of these lipid oxidation end-products do not appear to be very important with respect to increasing odorous fat sensitivity. The results obtained in the present study demonstrate the important role of saliva in the aroma release of EVOO, indicating that humans can perceive it differently in relation to their body mass index. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

A network of amygdala connections predict individual differences in trait anxiety.

PubMed

Greening, Steven G; Mitchell, Derek G V

2015-12-01

In this study we demonstrate that the pattern of an amygdala-centric network contributes to individual differences in trait anxiety. Individual differences in trait anxiety were predicted using maximum likelihood estimates of amygdala structural connectivity to multiple brain targets derived from diffusion-tensor imaging (DTI) and probabilistic tractography on 72 participants. The prediction was performed using a stratified sixfold cross validation procedure using a regularized least square regression model. The analysis revealed a reliable network of regions predicting individual differences in trait anxiety. Higher trait anxiety was associated with stronger connections between the amygdala and dorsal anterior cingulate cortex, an area implicated in the generation of emotional reactions, and inferior temporal gyrus and paracentral lobule, areas associated with perceptual and sensory processing. In contrast, higher trait anxiety was associated with weaker connections between amygdala and regions implicated in extinction learning such as medial orbitofrontal cortex, and memory encoding and environmental context recognition, including posterior cingulate cortex and parahippocampal gyrus. Thus, trait anxiety is not only associated with reduced amygdala connectivity with prefrontal areas associated with emotion modulation, but also enhanced connectivity with sensory areas. This work provides novel anatomical insight into potential mechanisms behind information processing biases observed in disorders of emotion. © 2015 Wiley Periodicals, Inc.