Negative Emotional Reactions to Challenging Behaviour and Staff Burnout: Two Replication Studies

ERIC Educational Resources Information Center

Rose, David; Horne, Sharon; Rose, John L.; Hastings, Richard P.

2004-01-01

Background: Hastings, R. P. ["American Journal on Mental Retardation" (2002) Vol. 107, pp. 455-467] hypothesized that staff negative emotional reactions to challenging behaviour might accumulate over time to affect staff well-being. Only one previous study (Mitchell, G.& Hastings, R. P. ["American Journal on Mental…

How to Facilitate Teachers' Understanding of Hypotheses and Predictions?

ERIC Educational Resources Information Center

Niaz, Mansoor

2011-01-01

The objective of this study was to facilitate inservice high school and university teachers' understanding of the difference between the terms "hypothesis" and "prediction." The context for understanding these terms was Columbus's discovery of America (as in the previous study). Control group teachers (N = 94) were evaluated before the discussion…

Confirmation of the "protein-traffic-hypothesis" and the "protein-localization-hypothesis" using the diabetes-mellitus-type-1-knock-in and transgenic-murine-models and the trepitope sequences.

PubMed

Arneth, Borros

2012-10-01

As possible mechanisms to explain the emergence of autoimmune diseases, the current author has suggested in earlier papers two new pathways: the "protein localization hypothesis" and the "protein traffic hypothesis". The "protein localization hypothesis" states that an autoimmune disease develops if a protein accumulates in a previously unoccupied compartment, that did not previously contain that protein. Similarly, the "protein traffic hypothesis" states that a sudden error within the transport of a certain protein leads to the emergence of an autoimmune disease. The current article discusses the usefulness of the different commercially available transgenic murine models of diabetes mellitus type 1 to confirm the aforementioned hypotheses. This discussion shows that several transgenic murine models of diabetes mellitus type 1 are in-line and confirm the aforementioned hypotheses. Furthermore, these hypotheses are additionally inline with the occurrence of several newly discovered protein sequences, the so-called trepitope sequences. These sequences modulate the immune response to certain proteins. The current study analyzed to what extent the hypotheses are supported by the occurrence of these new sequences. Thereby the occurrence of the trepitope sequences provides additional evidence supporting the aforementioned hypotheses. Both the "protein localization hypothesis" and the "protein traffic hypothesis" have the potential to lead to new causal therapy concepts. The "protein localization hypothesis" and the "protein traffic hypothesis" provide conceptional explanations for the diabetes mouse models as well as for the newly discovered trepitope sequences. Copyright © 2012 Elsevier Ltd. All rights reserved.

Price competition in the Chinese pharmaceutical market.

PubMed

Wang, Y Richard

2006-06-01

We study price competition between high-quality global products and low-quality local products in a developing country, i.e., China, Nearly all previous studies on pharmaceutical price competition focused on developed countries with bioequivalent generics. In China, local generic products are not bioequivalent and are deemed of lower quality, while global products in the same class are considered similar in quality and better substitutes. We hypothesize that local generic competition drives down local product price but not global product price. In addition, we hypothesize that therapeutic competition among similar global products lowers global product price. Our empirical results support both hypotheses. Number of local generic competitors has a significantly negative effect on local product price but no effect on global product price, while number of global therapeutic competitors has a significantly negative effect on global product price. Policy changes that encourage bioequivalent local products and accelerate global product approvals will enhance price competition in China.

A Study of Cleft Palate Speakers with Marginal Velopharyngeal Competence.

ERIC Educational Resources Information Center

Hardin, M. A.; And Others

1986-01-01

The study examined a previously hypothesized model for a subgroup of cleft palate speakers with marginal velopharyngeal competence during speech. Evaluation of 52 5- and 6-year-olds with appropriate lateral X-ray results indicated that most met fewer than three of the other five criteria required by the model. (Author/DB)

Chicken bile Matrix metalloproteinase; its characterization and significance

USDA-ARS?s Scientific Manuscript database

Previous studies from our lab had shown that the avian bile was rich in matrix metalloproteinase (MMP), enzymes implicated in the degradation of extracellular matrices (ECM) such as collagens and proteoglycans. We hypothesized that bile MMP may be evolutionarily associated with the digestion of ECM ...

Why and when workplace ostracism inhibits organizational citizenship behaviors: An organizational identification perspective.

PubMed

Wu, Chia-Huei; Liu, Jun; Kwan, Ho Kwong; Lee, Cynthia

2016-03-01

Why and when do employees respond to workplace ostracism by withholding their engagement in citizenship behavior? Beyond perspectives proposed in past studies, we offer a new account based on a social identity perspective and propose that workplace ostracism decreases citizenship behavior by undermining employees' identification with the organization. We also theorize that perceived job mobility influences the extent to which employees identify with the organization when being ostracized. These hypotheses were examined in two time-lagged studies conducted in China. The proposed hypotheses were supported by results in Study 1, and findings were generally replicated in Study 2, where effects of other known mediators (i.e., organization-based self-esteem, job engagement, and felt obligation toward the organization) and moderators (i.e., collectivism, power distance, and future orientation) suggested by previous perspectives were controlled. Results of Study 2 provided further support of the hypothesized directional effect of workplace ostracism on citizenship behavior via organizational identification. Our studies support the identification perspective in understanding workplace ostracism and also strengthen the application of this perspective in understanding workplace aggression broadly. (c) 2016 APA, all rights reserved).

Children's Socialization into Sport: A Replication.

ERIC Educational Resources Information Center

Standefer, Christine L.; And Others

This investigation sought to replicate a previous study (Greendorfer and Lewko, 1978) on children's socialization into sport. It was hypothesized that family members, specifically fathers, were the most significant predictors of male and female sport participation, followed by the peer group and teachers, respectively. A Sport Interest Inventory…

How job demands affect partners' experience of exhaustion: integrating work-family conflict and crossover theory.

PubMed

Bakker, Arnold B; Demerouti, Evangelia; Dollard, Maureen F

2008-07-01

This study among 168 couples of dual-earner parents uses insights from previous work-family conflict and crossover research to propose an integrative model delineating how job demands experienced by men and women carry over to the home domain. The authors hypothesized that for both men and women, job demands foster their own work-family conflict (WFC), which in turn contributes to their partners' home demands, family-work conflict (FWC), and exhaustion. In addition, they hypothesized that social undermining mediates the relationship between individuals' WFC and their partners' home demands. The results of structural equation modeling analyses provided strong support for the proposed model. The hypothesis that gender would moderate the model relationships was rejected. These findings integrate previous findings on work-family conflict and crossover theories and suggest fluid boundaries between the work and home domains.

Effects of snow on fisher and marten distributions in Idaho

Treesearch

Nathan Albrecht; C. Heusser; M. Schwartz; J. Sauder; R. Vinkey

2013-01-01

Studies have suggested that deep snow may limit fisher (Martes pennanti) distribution, and that fisher populations may in turn limit marten (Martes americana) distribution. We tested these hypotheses in the Northern Rocky Mountains of Idaho, a region which differs from previous study areas in its climate and relative fisher and marten abundance, but in which very...

Exploring Multiple Patterns of Faculty Productivity in STEM Disciplines at Doctoral Universities

ERIC Educational Resources Information Center

Liu, Ying

2010-01-01

This study is one of only a few that attempts to examine simultaneously faculty productivity in teaching, research, and service. The research is guided by a conceptual model built from several branches of the literature on career stage theory, motivation theory, and previous studies of faculty productivity. The model hypothesizes that faculty…

Impact of scaffolding and question structure on the gender gap

NASA Astrophysics Data System (ADS)

Dawkins, Hillary; Hedgeland, Holly; Jordan, Sally

2017-12-01

We address previous hypotheses about possible factors influencing the gender gap in attainment in physics. Specifically, previous studies claim that scaffolding may preferentially benefit female students, and we present some alternative conclusions surrounding this hypothesis. By taking both student attainment level and the degree of question scaffolding into account, we identify questions that exhibit real bias in favor of male students. We find that both multidimensional context and use of diagrams are common elements of such questions.

Brain Networks Shaping Religious Belief

PubMed Central

Deshpande, Gopikrishna; Krueger, Frank; Thornburg, Matthew P.; Grafman, Jordan Henry

2014-01-01

Abstract We previously demonstrated with functional magnetic resonance imaging (fMRI) that religious belief depends upon three cognitive dimensions, which can be mapped to specific brain regions. In the present study, we considered these co-activated regions as nodes of three networks each one corresponding to a particular dimension, corresponding to each dimension and examined the causal flow within and between these networks to address two important hypotheses that remained untested in our previous work. First, we hypothesized that regions involved in theory of mind (ToM) are located upstream the causal flow and drive non-ToM regions, in line with theories attributing religion to the evolution of ToM. Second, we hypothesized that differences in directional connectivity are associated with differences in religiosity. To test these hypotheses, we performed a multivariate Granger causality-based directional connectivity analysis of fMRI data to demonstrate the causal flow within religious belief-related networks. Our results supported both hypotheses. Religious subjects preferentially activated a pathway from inferolateral to dorsomedial frontal cortex to monitor the intent and involvement of supernatural agents (SAs; intent-related ToM). Perception of SAs engaged pathways involved in fear regulation and affective ToM. Religious beliefs are founded both on propositional statements for doctrine, but also on episodic memory and imagery. Beliefs based on doctrine engaged a pathway from Broca's to Wernicke's language areas. Beliefs related to everyday life experiences engaged pathways involved in imagery. Beliefs implying less involved SAs and evoking imagery activated a pathway from right lateral temporal to occipital regions. This pathway was more active in non-religious compared to religious subjects, suggesting greater difficulty and procedural demands for imagining and processing the intent of SAs. Insights gained by Granger connectivity analysis inform us about the causal binding of individual regions activated during religious belief processing. PMID:24279687

Brain networks shaping religious belief.

PubMed

Kapogiannis, Dimitrios; Deshpande, Gopikrishna; Krueger, Frank; Thornburg, Matthew P; Grafman, Jordan Henry

2014-02-01

We previously demonstrated with functional magnetic resonance imaging (fMRI) that religious belief depends upon three cognitive dimensions, which can be mapped to specific brain regions. In the present study, we considered these co-activated regions as nodes of three networks each one corresponding to a particular dimension, corresponding to each dimension and examined the causal flow within and between these networks to address two important hypotheses that remained untested in our previous work. First, we hypothesized that regions involved in theory of mind (ToM) are located upstream the causal flow and drive non-ToM regions, in line with theories attributing religion to the evolution of ToM. Second, we hypothesized that differences in directional connectivity are associated with differences in religiosity. To test these hypotheses, we performed a multivariate Granger causality-based directional connectivity analysis of fMRI data to demonstrate the causal flow within religious belief-related networks. Our results supported both hypotheses. Religious subjects preferentially activated a pathway from inferolateral to dorsomedial frontal cortex to monitor the intent and involvement of supernatural agents (SAs; intent-related ToM). Perception of SAs engaged pathways involved in fear regulation and affective ToM. Religious beliefs are founded both on propositional statements for doctrine, but also on episodic memory and imagery. Beliefs based on doctrine engaged a pathway from Broca's to Wernicke's language areas. Beliefs related to everyday life experiences engaged pathways involved in imagery. Beliefs implying less involved SAs and evoking imagery activated a pathway from right lateral temporal to occipital regions. This pathway was more active in non-religious compared to religious subjects, suggesting greater difficulty and procedural demands for imagining and processing the intent of SAs. Insights gained by Granger connectivity analysis inform us about the causal binding of individual regions activated during religious belief processing.

Bayesian meta-analysis of Cronbach's coefficient alpha to evaluate informative hypotheses.

PubMed

Okada, Kensuke

2015-12-01

This paper proposes a new method to evaluate informative hypotheses for meta-analysis of Cronbach's coefficient alpha using a Bayesian approach. The coefficient alpha is one of the most widely used reliability indices. In meta-analyses of reliability, researchers typically form specific informative hypotheses beforehand, such as 'alpha of this test is greater than 0.8' or 'alpha of one form of a test is greater than the others.' The proposed method enables direct evaluation of these informative hypotheses. To this end, a Bayes factor is calculated to evaluate the informative hypothesis against its complement. It allows researchers to summarize the evidence provided by previous studies in favor of their informative hypothesis. The proposed approach can be seen as a natural extension of the Bayesian meta-analysis of coefficient alpha recently proposed in this journal (Brannick and Zhang, 2013). The proposed method is illustrated through two meta-analyses of real data that evaluate different kinds of informative hypotheses on superpopulation: one is that alpha of a particular test is above the criterion value, and the other is that alphas among different test versions have ordered relationships. Informative hypotheses are supported from the data in both cases, suggesting that the proposed approach is promising for application. Copyright © 2015 John Wiley & Sons, Ltd.

Can Arousal Modulate Response Inhibition?

ERIC Educational Resources Information Center

Weinbach, Noam; Kalanthroff, Eyal; Avnit, Amir; Henik, Avishai

2015-01-01

The goal of the present study was to examine if and how arousal can modulate response inhibition. Two competing hypotheses can be drawn from previous literature. One holds that alerting cues that elevate arousal should result in an impulsive response and therefore impair response inhibition. The other suggests that alerting enhances processing of…

Adaptive Mechanisms for Treating Missing Information: A Simulation Study

ERIC Educational Resources Information Center

Garcia-Retamero, Rocio; Rieskamp, Jorg

2008-01-01

People often make inferences with incomplete information. Previous research has led to a mixed picture of how people treat missing information. To explain these results, the authors follow the Brunswikian perspective on human inference and hypothesize that the mechanism's accuracy for treating missing information depends on how it is distributed…

Vegetated land cover near residence is associated with reduced allostatic load and improved biomarkers of neuroendocrine, metabolic and immune functions

EPA Science Inventory

Abstract Background: Greater exposure to urban green spaces has been linked to reduced risks of depression, cardiovascular disease, diabetes and premature death. Alleviation of chronic stress is a hypothesized pathway to improved health. Previous studies linked chronic stress wit...

A Multivariate Model of Achievement in Geometry

ERIC Educational Resources Information Center

Bailey, MarLynn; Taasoobshirazi, Gita; Carr, Martha

2014-01-01

Previous studies have shown that several key variables influence student achievement in geometry, but no research has been conducted to determine how these variables interact. A model of achievement in geometry was tested on a sample of 102 high school students. Structural equation modeling was used to test hypothesized relationships among…

Dimensions of Psychopathy and Their Relationships to Cognitive Functioning in Children

ERIC Educational Resources Information Center

Fontaine, Nathalie; Barker, Edward D.; Salekin, Randall T.; Viding, Essi

2008-01-01

Individuals with psychopathic traits are hypothesized to be free of intellectual deficits and possibly even to exhibit good cognitive abilities. Previous studies, based on clinical and incarcerated youth, have shown inconsistent findings. We investigated the relationships between different dimensions of psychopathy (callous/unemotional traits,…

Influences of Creative Personality and Working Environment on the Research Productivity of Business School Faculty

ERIC Educational Resources Information Center

Kim, Kihwan; Choi, Suk Bong

2017-01-01

Previous research on creative working environments has focused on business organizations. This study examined the influence of creative personality and creative working environment on the research productivity of business faculty. It was hypothesized that creative personality, family support, colleague support, research resources, and workload…

Do You Have to be Angry to be Aggressive?

ERIC Educational Resources Information Center

Wienir, Paul L.

Seven hypotheses regarding the role of anger for aggressive behavior were testes in an experimental exchange situation using male children as subjects. In previous studies, anger had not actually been employed as the intervening variable in a provocation/aggressive cue-aggression model. The results indicate a strong relationship between…

Brief Report: Stereotypes in Autism Revisited

ERIC Educational Resources Information Center

Kirchner, Jennifer Christina; Schmitz, Florian; Dziobek, Isabel

2012-01-01

Autism involves core impairments in social cognition. Given that social learning underlies the acquisition of stereotypes, it was hypothesized that use of stereotypes would be reduced in autism. Contrary to this prediction, previous studies found the same use of stereotypes in autistic individuals as in controls. Measurement of stereotypes,…

Maltase-glucoamylase: Mucosal regulator of prandial starch glucogenesis and complimentary hepatic gluconeogenesis of mice

USDA-ARS?s Scientific Manuscript database

In previous studies we have shown that maltase-glucoamylase (Mgam) is required for efficient starch digestion and insulin response to starch feeding. It was hypothesized that the slower rate of starch digestion by residual sucrase-isomaltase (Si) maltase failed to regulate gluconeogenesis. Here, rat...

Enhanced Cardiac Perception Is Associated with Increased Susceptibility to Framing Effects

ERIC Educational Resources Information Center

Sutterlin, Stefan; Schulz, Stefan M.; Stumpf, Theresa; Pauli, Paul; Vogele, Claus

2013-01-01

Previous studies suggest in line with dual process models that interoceptive skills affect controlled decisions via automatic or implicit processing. The "framing effect" is considered to capture implicit effects of task-irrelevant emotional stimuli on decision-making. We hypothesized that cardiac awareness, as a measure of interoceptive…

Gain versus loss framing in adherence-promoting communication targeting patients with chronic diseases: the moderating effect of individual time perspective.

PubMed

Zhao, Xiaoquan; Villagran, Melinda M; Kreps, Gary L; McHorney, Colleen

2012-01-01

This study investigated the joint effect of message framing and time perspective in adherence-promoting communication targeting patients with chronic diseases. Based on previous framing and time perspective research, it was hypothesized that the gain frame would show an advantage over the loss frame among future-oriented patients; for present-oriented patients, it was hypothesized that the framing effect would be relatively indistinct. In total, 1,108 currently nonadherent patients with chronic disease participated in an experiment where they were randomly assigned to either gain- or loss-framed messages addressing key beliefs underlying their nonadherence or a no-message control condition. Intention and attitude regarding future adherence as well as message perceptions were measured after message presentation. Results of this study generally supported the hypotheses. Message topics-whether the messages addressed patients' perceived need for medications or concerns about side effects-did not moderate the effect of framing or the interaction between framing and time perspective. Theoretical and practical implications are discussed.

Cumulative risk hypothesis: Predicting and preventing child maltreatment recidivism.

PubMed

Solomon, David; Åsberg, Kia; Peer, Samuel; Prince, Gwendolyn

2016-08-01

Although Child Protective Services (CPS) and other child welfare agencies aim to prevent further maltreatment in cases of child abuse and neglect, recidivism is common. Having a better understanding of recidivism predictors could aid in preventing additional instances of maltreatment. A previous study identified two CPS interventions that predicted recidivism: psychotherapy for the parent, which was related to a reduced risk of recidivism, and temporary removal of the child from the parent's custody, which was related to an increased recidivism risk. However, counter to expectations, this previous study did not identify any other specific risk factors related to maltreatment recidivism. For the current study, it was hypothesized that (a) cumulative risk (i.e., the total number of risk factors) would significantly predict maltreatment recidivism above and beyond intervention variables in a sample of CPS case files and that (b) therapy for the parent would be related to a reduced likelihood of recidivism. Because it was believed that the relation between temporary removal of a child from the parent's custody and maltreatment recidivism is explained by cumulative risk, the study also hypothesized that that the relation between temporary removal of the child from the parent's custody and recidivism would be mediated by cumulative risk. After performing a hierarchical logistic regression analysis, the first two hypotheses were supported, and an additional predictor, psychotherapy for the child, also was related to reduced chances of recidivism. However, Hypothesis 3 was not supported, as risk did not significantly mediate the relation between temporary removal and recidivism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Effects of Game Design Patterns on Basic Life Support Training Content

ERIC Educational Resources Information Center

Kelle, Sebastian; Klemke, Roland; Specht, Marcus

2013-01-01

Based on a previous analysis of game design patterns and related effects in an educational scenario, the following paper presents an experimental study. In the study a course for Basic Life Support training has been evaluated and two game design patterns have been applied to the course. The hypotheses evaluated in this paper relate to game design…

Role Stress Revisited: Job Structuring Antecedents, Work Outcomes, and Moderating Effects of Locus of Control

ERIC Educational Resources Information Center

Conley, Sharon; You, Sukkyung

2014-01-01

A previous study examined role stress in relation to work outcomes; in this study, we added job structuring antecedents to a model of role stress and examined the moderating effects of locus of control. Structural equation modeling was used to assess the plausibility of our conceptual model, which specified hypothesized linkages among teachers'…

Morphology-based phylogeny of the suckermouth armored catfishes, with emphasis on the Neoplecostominae (Teleostei: Siluriformes: Loricariidae).

PubMed

Pereira, Edson H L; Reis, Roberto E

2017-05-11

A phylogenetic study of the Loricariidae with emphasis on the Neoplecostominae is presented based on a maximum parsimony analysis of 268 phenotypic characters encompassing osteology, arthrology, and external morphology. Results support previous hypotheses of the monophyly of the Neoplecostominae and each of the included genera: Hirtella, Isbrueckerichthys, Kronichthys, Neoplecostomus, Pareiorhaphis, and Pareiorhina. In addition, previously undiscovered diversity was revealed within the subfamily as an additional genus-level taxon, herein described as Euryochus. Relationships among neoplecostomine genera are: (Kronichthys (Euryochus ((Hirtella + Pareiorhaphis) (Pareiorhina (Isbrueckerichthys + Neoplecostomus))))). Additional undescribed diversity was also detected among most neoplecostomine genera and the Hypoptopomatinae. In addition, recently discovered genera Nannoplecostomus and Microplecostomus were included in the analysis, and were identified as sequential sister-taxa to Neoplecostominae + Hypoptopomatinae, which are currently not included in any subfamily and regarded as incertae sedis in Loricariidae. The three species of Lithogenes were included in an encompassing phylogenetic analysis for the first time, and were identified as a monophyletic unit and sister group to all remaining loricariids. The other loricariid subfamilies were also corroborated as monophyletic, and presented the following interrelationships (Lithogeninae (Delturinae (Loricariinae (Hypostominae (Nannoplecostomus (Microplecostomus (Hypoptopomatinae + Neoplecostominae). The Neoplecostominae and its genera are phylogenetically diagnosed, and hypothesized relationships are compared to those of previous morphological and molecular phylogenetic studies.

Teasing in hierarchical and intimate relations.

PubMed

Keltner, D; Young, R C; Heerey, E A; Oemig, C; Monarch, N D

1998-11-01

Following E. Goffman's (1967) face threat analysis of social interaction, it was hypothesized that the aggressive, playful content of teasing would vary according to social status and relational satisfaction, personality, role as teaser or target, and gender. These 4 hypotheses were tested in analyses of the teasing among fraternity members (Study 1) and romantic couples (Study 2). Consistent with a face threat analysis of teasing, low-status fraternity members and satisfied romantic partners teased in more prosocial ways, defined by reduced face threat and increased redressive action. Some findings indicate that disagreeable individuals teased in less prosocial ways, consistent with studies of bullying. Targets reported more negative emotion than teasers. Although female and male romantic partners teased each other in similar ways, women found being the target of teasing more aversive, consistent with previous speculation.

Phylogeny, biogeography and diversification patterns of side-necked turtles (Testudines: Pleurodira)

PubMed Central

Langer, Max C.; Sterli, Juliana

2018-01-01

Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa–Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous–Palaeogene or the Eocene–Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages. PMID:29657780

Phylogeny, biogeography and diversification patterns of side-necked turtles (Testudines: Pleurodira)

NASA Astrophysics Data System (ADS)

Ferreira, Gabriel S.; Bronzati, Mario; Langer, Max C.; Sterli, Juliana

2018-03-01

Pleurodires or side-necked turtles are today restricted to freshwater environments of South America, Africa-Madagascar and Australia, but in the past they were distributed much more broadly, being found also on Eurasia, India and North America, and marine environments. Two hypotheses were proposed to explain this distribution; in the first, vicariance would have shaped the current geographical distribution and, in the second, extinctions constrained a previously widespread distribution. Here, we aim to reconstruct pleurodiran biogeographic history and diversification patterns based on a new phylogenetic hypothesis recovered from the analysis of the largest morphological dataset yet compiled for the lineage, testing which biogeographical process prevailed during its evolutionary history. The resulting topology generally agrees with previous hypotheses of the group and shows that most diversification shifts were related to the exploration of new niches, e.g. littoral or marine radiations. In addition, as other turtles, pleurodires do not seem to have been much affected by either the Cretaceous-Palaeogene or the Eocene-Oligocene mass extinctions. The biogeographic analyses highlight the predominance of both anagenetic and cladogenetic dispersal events and support the importance of transoceanic dispersals as a more common driver of area changes than previously thought, agreeing with previous studies with other non-turtle lineages.

The Effects of Partnership Management on Supply Chain Cooperative Performance: A Case Study of High-Tech Industry

NASA Astrophysics Data System (ADS)

Wu, Mei-Ying; Chang, Yun-Ju; Weng, Yung-Chien

2009-08-01

With the structural change of global supply chains, the relationship between manufacturers and suppliers has transformed into a long-term partnership. Thus, this study aims to explore the partnership between manufacturers and suppliers in Taiwan's high-tech industry. Four constructs, including partner characteristic, partnership quality, partnership closeness, and cooperative performance, induced from previous literatures are used to construct the research framework and hypotheses. A questionnaire survey is then performed on executives and staffs involved in the high-tech industry. The proposed framework and hypotheses are empirically validated through confirmatory factory analysis and structural equation modeling. It is expected that the research findings can serve as a reference for Taiwan's high-tech industry on building partnerships.

Cancer risks near nuclear facilities: the importance of research design and explicit study hypotheses.

PubMed

Wing, Steve; Richardson, David B; Hoffmann, Wolfgang

2011-04-01

In April 2010, the U.S. Nuclear Regulatory Commission asked the National Academy of Sciences to update a 1990 study of cancer risks near nuclear facilities. Prior research on this topic has suffered from problems in hypothesis formulation and research design. We review epidemiologic principles used in studies of generic exposure-response associations and in studies of specific sources of exposure. We then describe logical problems with assumptions, formation of testable hypotheses, and interpretation of evidence in previous research on cancer risks near nuclear facilities. Advancement of knowledge about cancer risks near nuclear facilities depends on testing specific hypotheses grounded in physical and biological mechanisms of exposure and susceptibility while considering sample size and ability to adequately quantify exposure, ascertain cancer cases, and evaluate plausible confounders. Next steps in advancing knowledge about cancer risks near nuclear facilities require studies of childhood cancer incidence, focus on in utero and early childhood exposures, use of specific geographic information, and consideration of pathways for transport and uptake of radionuclides. Studies of cancer mortality among adults, cancers with long latencies, large geographic zones, and populations that reside at large distances from nuclear facilities are better suited for public relations than for scientific purposes.

Molecular phylogenetics of the family Cyprinidae (Actinopterygii: Cypriniformes) as evidenced by sequence variation in the first intron of S7 ribosomal protein-coding gene: further evidence from a nuclear gene of the systematic chaos in the family.

PubMed

He, Shunping; Mayden, Richard L; Wang, Xuzheng; Wang, Wei; Tang, Kevin L; Chen, Wei-Jen; Chen, Yiyu

2008-03-01

The family Cyprinidae is the largest freshwater fish group in the world, including over 200 genera and 2100 species. The phylogenetic relationships of major clades within this family are simply poorly understood, largely because of the overwhelming diversity of the group; however, several investigators have advanced different hypotheses of relationships that pre- and post-date the use of shared-derived characters as advocated through phylogenetic systematics. As expected, most previous investigations used morphological characters. Recently, mitochondrial DNA (mtDNA) sequences and combined morphological and mtDNA investigations have been used to explore and advance our understanding of species relationships and test monophyletic groupings. Limitations of these studies include limited taxon sampling and a strict reliance upon maternally inherited mtDNA variation. The present study is the first endeavor to recover the phylogenetic relationships of the 12 previously recognized monophyletic subfamilies within the Cyprinidae using newly sequenced nuclear DNA (nDNA) for over 50 species representing members of the different previously hypothesized subfamily and family groupings within the Cyprinidae and from other cypriniform families as outgroup taxa. Hypothesized phylogenetic relationships are constructed using maximum parsimony and Basyesian analyses of 1042 sites, of which 971 sites were variable and 790 were phylogenetically informative. Using other appropriate cypriniform taxa of the families Catostomidae (Myxocyprinus asiaticus), Gyrinocheilidae (Gyrinocheilus aymonieri), and Balitoridae (Nemacheilus sp. and Beaufortia kweichowensis) as outgroups, the Cyprinidae is resolved as a monophyletic group. Within the family the genera Raiamas, Barilius, Danio, and Rasbora, representing many of the tropical cyprinids, represent basal members of the family. All other species can be classified into variably supported and resolved monophyletic lineages, depending upon analysis, that are consistent with or correspond to Barbini and Leuciscini. The Barbini includes taxa traditionally aligned with the subfamily Cyprininae sensu previous morphological revisionary studies by Howes (Barbinae, Labeoninae, Cyprininae and Schizothoracinae). The Leuciscini includes six other subfamilies that are mainly divided into three separate lineages. The relationships among genera and subfamilies are discussed as well as the possible origins of major lineages.

Sources of Science Self-Efficacy Beliefs of Middle School Students

ERIC Educational Resources Information Center

Britner, Shari L.; Pajares, Frank

2006-01-01

The purpose of this study was to investigate the degree to which A. Bandura's ([1997]) hypothesized sources of self-efficacy predict the science self-efficacy beliefs of middle school students (N = 319), to replicate previous findings that science self-efficacy predicts science achievement, and to explore how science self-efficacy and its…

An Analysis of Primary School Dropout Patterns in Honduras

ERIC Educational Resources Information Center

Sekiya, Takeshi; Ashida, Akemi

2017-01-01

This study hypothesized that repeating a grade is one reason why Honduran primary students drop out of school but not the main reason. Using longitudinal data, we analyzed student enrollment patterns up until students left school. The results revealed that many students dropped out suddenly without having previously repeated a grade, although many…

How Readability and Topic Incidence Relate to Performance on Mathematics Story Problems in Computer-Based Curricula

ERIC Educational Resources Information Center

Walkington, Candace; Clinton, Virginia; Ritter, Steven N.; Nathan, Mitchell J.

2015-01-01

Solving mathematics story problems requires text comprehension skills. However, previous studies have found few connections between traditional measures of text readability and performance on story problems. We hypothesized that recently developed measures of readability and topic incidence measured by text-mining tools may illuminate associations…

Prosodic Structure Shapes the Temporal Realization of Intonation and Manual Gesture Movements

ERIC Educational Resources Information Center

Esteve-Gibert, Nuria; Prieto, Pilar

2013-01-01

Purpose: Previous work on the temporal coordination between gesture and speech found that the prominence in gesture coordinates with speech prominence. In this study, the authors investigated the anchoring regions in speech and pointing gesture that align with each other. The authors hypothesized that (a) in contrastive focus conditions, the…

Teacher Work Context and Parent Involvement in Urban High Schools of Choice.

ERIC Educational Resources Information Center

Bauch, Patricia A.; Goldring, Ellen B.

2000-01-01

Uses findings from previous studies of teacher work context to hypothesize that some features of the school workplace may contribute to greater parent involvement in urban high schools, especially home-school communication and parent volunteering. Discusses the roles of communal school organization and a context of caring. (SLD)

A Disaggregate Study of the Effect of Unemployment Rates on Labor Supply.

ERIC Educational Resources Information Center

Fleisher, Belton M.; Parsons, Donald O.

The project focuses on two loosely-related hypotheses regarding a contradiction existing in the results of previous research on the relationship between labor force participation and unemployment. This contradiction is the persistent tendency of the estimated effect of unemployment on labor force participation--and hence estimates of "hidden…

Young dispersal of xerophil Nitraria lineages in intercontinental disjunctions of the Old World

Treesearch

Ming-Li Zhang; Kamshat Temirbayeva; Stewart C. Sanderson; X. Chen

2015-01-01

Many cases of intercontinental disjunct distributions of seed plants have been investigated, however few have concerned the continents of Eurasia (mainly Central Asia), Africa, and Australia, especially the xerophytic lineages are lacking. Nitraria (Nitrariaceae) is just one of these xerophytic lineages. Previous Nitraria studies have hypothesized either Africa as the...

Symptom Prevalence of ADHD in a Community Residential Substance Abuse Treatment Program

ERIC Educational Resources Information Center

McAweeney, Mary; Rogers, Nikki L.; Huddleston, Carole; Moore, Dennis; Gentile, Julie P.

2010-01-01

Objective: ADHD is a common comorbid condition with substance use disorder. This study seeks to examine the discrepancy in the prevalence rate between those previously diagnosed with ADHD and those diagnosed while in treatment. It is hypothesized that clients with ADHD would have earlier unsuccessful terminations from treatment than non-ADHD…

Sexual Orientation and Psychological Distress in Adolescence: Examining Interpersonal Stressors and Social Support Processes

ERIC Educational Resources Information Center

Ueno, Koji

2005-01-01

Adolescents with homosexual and bisexual orientations have higher levels of psychological distress than other adolescents. Drawing from previous studies, I hypothesize that this epidemiological pattern is due largely to the interpersonal problems that sexual minorities experience at home and at school. Analysis of longitudinal data based on a…

Cellular uptake and metabolism of curcuminoids in monocytes/macrophages: regulatory effects on lipid accumulation

USDA-ARS?s Scientific Manuscript database

We previously showed that curcumin (CUR) may increase lipid accumulation in cultured THP-1 monocytes/macrophages, but tetrahydrocurcumin (THC), an in vivo metabolite of CUR, had no such effect. In the present study, we have hypothesized that different cellular uptake and/or metabolism of CUR and THC...

Keeping Them Happy: Job Satisfaction, Personality, and Attitudes toward Disability in Predicting Counselor Job Retention

ERIC Educational Resources Information Center

Lawrence, Emily R.; Glidden, Laraine M.; Jobe, Brian M.

2006-01-01

Employee retention was studied in 48 counselors working at a summer camp for children and adults with disabilities. We hypothesized that attitudes toward persons with disabilities, personality characteristics of counselors, job satisfaction, and previous counselor experience would predict whether counselors would elect to return to work the…

Predictive hypotheses are ineffectual in resolving complex biochemical systems.

PubMed

Fry, Michael

2018-03-20

Scientific hypotheses may either predict particular unknown facts or accommodate previously-known data. Although affirmed predictions are intuitively more rewarding than accommodations of established facts, opinions divide whether predictive hypotheses are also epistemically superior to accommodation hypotheses. This paper examines the contribution of predictive hypotheses to discoveries of several bio-molecular systems. Having all the necessary elements of the system known beforehand, an abstract predictive hypothesis of semiconservative mode of DNA replication was successfully affirmed. However, in defining the genetic code whose biochemical basis was unclear, hypotheses were only partially effective and supplementary experimentation was required for its conclusive definition. Markedly, hypotheses were entirely inept in predicting workings of complex systems that included unknown elements. Thus, hypotheses did not predict the existence and function of mRNA, the multiple unidentified components of the protein biosynthesis machinery, or the manifold unknown constituents of the ubiquitin-proteasome system of protein breakdown. Consequently, because of their inability to envision unknown entities, predictive hypotheses did not contribute to the elucidation of cation theories remained the sole instrument to explain complex bio-molecular systems, the philosophical question of alleged advantage of predictive over accommodative hypotheses became inconsequential.

We'll never get past the glass ceiling! Meta-stereotyping, world-views and perceived relative group-worth.

PubMed

Owuamalam, Chuma; Zagefka, Hanna

2013-11-01

This article examines the implications of perceived negativity from members of a dominant outgroup on the world views and perceived relative group worth of members of disadvantaged groups. We hypothesized that concerns about the negative opinions a dominant outgroup is perceived to hold of the ingroup (i.e., meta-stereotypes) would undermine group members' views about societal fairness. We expected this trend to be mediated by recall of previous personal experiences of discrimination. We further hypothesized that members' views about societal fairness would predict their perception of the ingroup's worth relative to the outgroup - such that undermined views about societal fairness would be associated with lower perceived ingroup worth relative to the outgroup. Taken jointly, results from two studies using two real intergroup contexts support these hypotheses and are discussed in terms of their implications for the social mobility of members of disadvantaged groups. © 2012 The British Psychological Society.

Fourier power, subjective distance, and object categories all provide plausible models of BOLD responses in scene-selective visual areas

PubMed Central

Lescroart, Mark D.; Stansbury, Dustin E.; Gallant, Jack L.

2015-01-01

Perception of natural visual scenes activates several functional areas in the human brain, including the Parahippocampal Place Area (PPA), Retrosplenial Complex (RSC), and the Occipital Place Area (OPA). It is currently unclear what specific scene-related features are represented in these areas. Previous studies have suggested that PPA, RSC, and/or OPA might represent at least three qualitatively different classes of features: (1) 2D features related to Fourier power; (2) 3D spatial features such as the distance to objects in a scene; or (3) abstract features such as the categories of objects in a scene. To determine which of these hypotheses best describes the visual representation in scene-selective areas, we applied voxel-wise modeling (VM) to BOLD fMRI responses elicited by a set of 1386 images of natural scenes. VM provides an efficient method for testing competing hypotheses by comparing predictions of brain activity based on encoding models that instantiate each hypothesis. Here we evaluated three different encoding models that instantiate each of the three hypotheses listed above. We used linear regression to fit each encoding model to the fMRI data recorded from each voxel, and we evaluated each fit model by estimating the amount of variance it predicted in a withheld portion of the data set. We found that voxel-wise models based on Fourier power or the subjective distance to objects in each scene predicted much of the variance predicted by a model based on object categories. Furthermore, the response variance explained by these three models is largely shared, and the individual models explain little unique variance in responses. Based on an evaluation of previous studies and the data we present here, we conclude that there is currently no good basis to favor any one of the three alternative hypotheses about visual representation in scene-selective areas. We offer suggestions for further studies that may help resolve this issue. PMID:26594164

On the impact of masking and blocking hypotheses for measuring the efficacy of new tuberculosis vaccines.

PubMed

Arregui, Sergio; Sanz, Joaquín; Marinova, Dessislava; Martín, Carlos; Moreno, Yamir

2016-01-01

Over the past 60 years, the Mycobacterium bovis bacille Calmette-Guérin (BCG) has been used worldwide to prevent tuberculosis (TB). However, BCG has shown a very variable efficacy in different trials, offering a wide range of protection in adults against pulmonary TB. One of the most accepted hypotheses to explain these inconsistencies points to the existence of a pre-existing immune response to antigens that are common to environmental sources of mycobacterial antigens and Mycobacterium tuberculosis. Specifically, two different mechanisms have been hypothesized to explain this phenomenon: the masking and the blocking effects. According to masking hypothesis, previous sensitization confers some level of protection against TB that masks vaccine's effects. In turn, the blocking hypothesis postulates that previous immune response prevents vaccine taking of a new TB vaccine. In this work we introduce a series of models to discriminate between masking and blocking mechanisms and address their relative likelihood. We apply our methodology to the data reported by BCG-REVAC clinical trials, which were specifically designed for studying BCG efficacy variability. Our results yield estimates that are consistent with high levels of blocking (41% in Manaus -95% CI [14-68]- and 96% in Salvador -95% CI [52-100]-). Moreover, we also show that masking does not play any relevant role in modifying vaccine's efficacy either alone or in addition to blocking. The quantification of these effects around a plausible model constitutes a relevant step towards impact evaluation of novel anti-tuberculosis vaccines, which are susceptible of being affected by similar effects, especially if applied on individuals previously exposed to mycobacterial antigens.

Investigating the effect of previous treatments on wheat biomass over multiple spatial frequencies

NASA Astrophysics Data System (ADS)

Milne, A. E.; Castellanos, M. T.; Cartagena, M. C.; Tarquis, A. M.; Lark, R. M.

2010-09-01

In this study we use the maximum overlap discrete packet transform (MODWPT) to investigate residual effects on wheat biomass of fertigation treatments applied to a previous crop. The wheat crop covered nine subplots from a previous experiment on melon response to fertigation. Each subplot had previously received a different level of applied nitrogen. Many factors affect wheat biomass, causing it to vary at different spatial frequencies. We hypothesize that these will include residual effects from fertilizer application (at relatively low spatial frequencies) and the local influence of individual plants from the previous melon crop (at high frequency). To test this hypothesis we use the MODWPT to identify the dominant spatial frequencies of wheat biomass variation, and analyse the relationship to both the previous fertilizer application and the location of individual melon plants in the previous crop. The MODWPT is particularly appropriate for this because it allows us first to identify the key spatial frequencies in the wheat biomass objectively and to analyse them, and their relationship to hypothesized driving factors without any assumptions of uniformity (stationarity) of wheat-biomass variation. The results showed that the applied nitrogen dominated the wheat biomass response, and that there was a noticeable component of wheat-biomass variation at the spatial frequency that corresponds to the melon cropping. We expected wheat biomass to be negatively correlated with the position of melons in the previous crop, due to uptake of the applied nitrogen. The MODWPT, which allows us to detect changes in correlation between variables at different frequencies, showed that such a relationship was found across part of the experiment but not uniformly.

Natural frequencies improve Bayesian reasoning in simple and complex inference tasks

PubMed Central

Hoffrage, Ulrich; Krauss, Stefan; Martignon, Laura; Gigerenzer, Gerd

2015-01-01

Representing statistical information in terms of natural frequencies rather than probabilities improves performance in Bayesian inference tasks. This beneficial effect of natural frequencies has been demonstrated in a variety of applied domains such as medicine, law, and education. Yet all the research and applications so far have been limited to situations where one dichotomous cue is used to infer which of two hypotheses is true. Real-life applications, however, often involve situations where cues (e.g., medical tests) have more than one value, where more than two hypotheses (e.g., diseases) are considered, or where more than one cue is available. In Study 1, we show that natural frequencies, compared to information stated in terms of probabilities, consistently increase the proportion of Bayesian inferences made by medical students in four conditions—three cue values, three hypotheses, two cues, or three cues—by an average of 37 percentage points. In Study 2, we show that teaching natural frequencies for simple tasks with one dichotomous cue and two hypotheses leads to a transfer of learning to complex tasks with three cue values and two cues, with a proportion of 40 and 81% correct inferences, respectively. Thus, natural frequencies facilitate Bayesian reasoning in a much broader class of situations than previously thought. PMID:26528197

Female Swedish backpackers in Vietnam: a hypotheses generating study on sexual health risks while travelling.

PubMed

Dahlman, Disa; Stafström, Martin

2013-01-01

According to previous studies, foreign travellers and backpackers are at increased risk of sexually transmitted infections (STI). Concurrently, STI incidence, especially Chlamydia, is increasing among young Swedes. Our objective was to investigate Swedish backpackers' own view of sexual health and risks while travelling, with the purpose to identify hypotheses for further, more extensive research. In-depth semi-structured interviews were carried out in Vietnam with four Swedish women in their early twenties. The interviewees had been travelling throughout South East Asia for a period of at least two weeks. There were large differences between the respondents regarding perceived health risks in relation to food safety, STI, and alcohol and drug use; and to what extent their behaviour while travelling deviated from their normal one. In contrast, the interviewees shared a perceived lack of knowledge about sexual health abroad. The study identified six hypotheses and suggestions for preventive measures that could be analysed in future research. The study demonstrated that sexual behaviour as well as attitudes and norms were strongly linked to the individual level, rather than to the group of backpackers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Assessment of Body Composition Using Whole Body Air-Displacement Plethysmography in Children with and without Developmental Coordination Disorder

ERIC Educational Resources Information Center

Cairney, John; Hay, John; Veldhuizen, Scott; Faught, Brent

2011-01-01

Developmental coordination disorder (DCD) is a neuro-developmental disorder characterized by poor fine and/or gross motor coordination. Children with DCD are hypothesized to be at increased risk for overweight and obesity from inactivity due to their motor coordination problems. Although previous studies have found evidence to support this…

Neurogenesis Interferes with the Retrieval of Remote Memories: Forgetting in Neurocomputational Terms

ERIC Educational Resources Information Center

Weisz, Victoria I.; Argibay, Pablo F.

2012-01-01

In contrast to models and theories that relate adult neurogenesis with the processes of learning and memory, almost no solid hypotheses have been formulated that involve a possible neurocomputational influence of adult neurogenesis on forgetting. Based on data from a previous study that implemented a simple but complete model of the main…

Body Satisfaction and Sexual Health Behaviors among New Zealand Secondary School Students

ERIC Educational Resources Information Center

Larson, Bridget K.; Clark, Terryann C.; Robinson, Elizabeth M.; Utter, Jennifer

2012-01-01

This population-based study of 2931 respondents to Youth07 (a cross-sectional survey of New Zealand secondary students' health) examines associations between weight-related variables and sexual risk-taking. It is hypothesized that girls who report poorer body satisfaction or previous weight-loss attempts will be: more likely to be currently…

A Study of Workplace Aggression as Related to Pedagogical Reform in Hong Kong Secondary Schools

ERIC Educational Resources Information Center

Tam, Frank Wai-ming

2013-01-01

Purpose: Previous research on pedagogical reforms has seldom looked at how reform may contribute to aggression in school organizations. The purpose of this paper is to hypothesize that teachers' disengagement from school mediates the tendency for teachers to manifest aggression when they are implementing pedagogical reform in school. Behind this…

Changes in immune and metabolic gut response in broilers fed beta-mannanase in beta-mannan containing diets

USDA-ARS?s Scientific Manuscript database

Beta-mannans, found in soy-based broiler feed, are known to cause physiological effects that are hypothesized to be related to gut inflammation. Previous studies have shown that the incorporation of beta-mannanase in the diet or as a supplement results in improvements to certain performance paramet...

Reforestation trials and secondary succession with three levels of overstory shade in the Grand Fir Mosaic ecosystem

Treesearch

Dennis E. Ferguson; John C. Byrne; Dale O. Coffen

2005-01-01

Grand Fir Mosaic habitats are difficult to regenerate because of pocket gophers (Thomomys talpoides) and successional plant communities dominated by bracken fern (Pteridium aquilinum) and western coneflower (Rudbeckia occidentalis). This study tested reforestation practices recommended by previous research, tested hypotheses about the effects of overstory shade on...

A comparision of cumulative-germination response of cheatgrass (Bromus Tectorum L.) and five perennial bunchgrass species to simulated field-temperature regimes

USDA-ARS?s Scientific Manuscript database

Cheatgrass (Bromus tectorum L.) has come to dominate millions of hectares of rangeland in the Intermountain western United States. Previous studies have hypothesized that one mechanism conferring a competitive advantage to this species is the ability to germinate rapidly at low temperatures in the ...

Expression of the ephrin receptor B2 in the embryonic chicken bursa of Fabricius

USDA-ARS?s Scientific Manuscript database

Chicken B-cells develop in a specific organ, the bursa of Fabricius. To understand the bursal microenvironment guiding B-cell development, previous studies identified ephrin (Eph) receptor B2 (EphB2) gene transcripts in the embryonic bursa. We hypothesize that the EphB2 receptors and their ligands r...

Effect of Cooperative Learning on Achievement of Students in General Science at Secondary Level

ERIC Educational Resources Information Center

Parveen, Qaisara; Batool, Sadia

2012-01-01

The aim of the study was to explore the effects of cooperative learning on General Science achievement among 9th class students. Based upon previous research literature it was hypothesized that significant difference existed between the mean posttest scores of General Science achievement of experimental group and control group. The pretest…

Effectiveness of Semantic Therapy for Word-Finding Difficulties in Pupils with Persistent Language Impairments: A Randomized Control Trial

ERIC Educational Resources Information Center

Ebbels, Susan H.; Nicoll, Hilary; Clark, Becky; Eachus, Beth; Gallagher, Aoife L.; Horniman, Karen; Jennings, Mary; McEvoy, Kate; Nimmo, Liz; Turner, Gail

2012-01-01

Background: Word-finding difficulties (WFDs) in children have been hypothesized to be caused at least partly by poor semantic knowledge. Therefore, improving semantic knowledge should decrease word-finding errors. Previous studies of semantic therapy for WFDs are inconclusive. Aims: To investigate the effectiveness of semantic therapy for…

Determinants of embryo development and quality in beef cattle: Effect of pre-ovulatory follicle size, CL volume, and serum concentrations of progesterone

USDA-ARS?s Scientific Manuscript database

Previous research indicates cows ovulating a small dominant follicle (<_ 12 mm) had lower pregnancy rates than cows ovulating a large follicle (> 12 mm). We hypothesized cows ovulating a small follicle would have delayed embryo development and decreased embryo quality. Objectives of this study wer...

Gender Differences in Figural Matrices: The Moderating Role of Item Design Features

ERIC Educational Resources Information Center

Arendasy, Martin E.; Sommer, Markus

2012-01-01

There is a heated debate on whether observed gender differences in some figural matrices in adults can be attributed to gender differences in inductive reasoning/G[subscript f] or differential item functioning and/or test bias. Based on previous studies we hypothesized that three specific item design features moderate the effect size of the gender…

'Thunder' - Shock waves in pre-biological organic synthesis.

NASA Technical Reports Server (NTRS)

Bar-Nun, A.; Tauber, M. E.

1972-01-01

Theoretical study of the gasdynamics and chemistry of lightning-produced shock waves in a postulated primordial reducing atmosphere. It is shown that the conditions are similar to those encountered in a previously performed shock-tube experiment which resulted in 36% of the ammonia in the original mixture being converted into amino acids. The calculations give the (very large) energy rate of about 0.4 cal/sq cm/yr available for amino acid production, supporting previous hypotheses that 'thunder' could have been responsible for efficient large-scale production of organic molecules serving as precursors of life.

Media mating I: newspaper "personals" ads of homosexual men.

PubMed

Laner, M R; Kamel, G W

1977-01-01

Based on a design used in previous research with heterosexuals "Personals" advertisements, this study reports a content analysis of 359 ads placed by male homosexuals. Following exchange theory, it was hypothesized that, as with heterosexuals, a favorable presentation of self would characterize the advertisements. Further hypotheses predicted that homosexual ads would be more frank than are heterosexual ads and more specific about goals for desired relationships, and that homosexual ads would reflect the "virilization" of the male homosexual subculture. All predictions were strongly supported. The overtly sexual explicitness of many of the advertisements was explained on the basis of differences between same- and cross-sex relationships, and male/female differences in conceptualizing "love."

A Bayesian Method for Evaluating and Discovering Disease Loci Associations

PubMed Central

Jiang, Xia; Barmada, M. Michael; Cooper, Gregory F.; Becich, Michael J.

2011-01-01

Background A genome-wide association study (GWAS) typically involves examining representative SNPs in individuals from some population. A GWAS data set can concern a million SNPs and may soon concern billions. Researchers investigate the association of each SNP individually with a disease, and it is becoming increasingly commonplace to also analyze multi-SNP associations. Techniques for handling so many hypotheses include the Bonferroni correction and recently developed Bayesian methods. These methods can encounter problems. Most importantly, they are not applicable to a complex multi-locus hypothesis which has several competing hypotheses rather than only a null hypothesis. A method that computes the posterior probability of complex hypotheses is a pressing need. Methodology/Findings We introduce the Bayesian network posterior probability (BNPP) method which addresses the difficulties. The method represents the relationship between a disease and SNPs using a directed acyclic graph (DAG) model, and computes the likelihood of such models using a Bayesian network scoring criterion. The posterior probability of a hypothesis is computed based on the likelihoods of all competing hypotheses. The BNPP can not only be used to evaluate a hypothesis that has previously been discovered or suspected, but also to discover new disease loci associations. The results of experiments using simulated and real data sets are presented. Our results concerning simulated data sets indicate that the BNPP exhibits both better evaluation and discovery performance than does a p-value based method. For the real data sets, previous findings in the literature are confirmed and additional findings are found. Conclusions/Significance We conclude that the BNPP resolves a pressing problem by providing a way to compute the posterior probability of complex multi-locus hypotheses. A researcher can use the BNPP to determine the expected utility of investigating a hypothesis further. Furthermore, we conclude that the BNPP is a promising method for discovering disease loci associations. PMID:21853025

Antihistamine Use in Early Pregnancy and Risk of Birth Defects

PubMed Central

Li, Qian; Mitchell, Allen A.; Werler, Martha M.; Yau, Wai-Ping; Hernández-Díaz, Sonia

2014-01-01

Background Several studies have reported an association between use of specific antihistamines in early pregnancy and certain specific birth defects. Objective To test 16 previously-hypothesized associations between specific antihistamines and specific birth defects, and identify possible new associations. Methods We used 1998-2010 data from the Slone Epidemiology Center Birth Defects Study, a multicenter case-control surveillance program of birth defects in North America. Mothers were interviewed within six months of delivery about demographic, reproductive, medical, and behavioral factors, and details on use of prescription and non-prescription medications. We compared 1st trimester exposure to specific antihistamines between 13,213 infants with specific malformations and 6,982 non-malformed controls, using conditional logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs), with adjustment for potential confounders, including indication for use. Results Overall, 13.7% of controls were exposed to antihistamines during the 1st trimester. The most commonly-used medications were diphenhydramine (4.2%), loratadine (3.1%), doxylamine (1.9%), and chlorpheniramine (1.7%). Where estimates were stable, none supported the previously-hypothesized associations. Among over 100 exploratory comparisons of other specific antihistamine/defect pairs, 14 had ORs ≥1.5 of which 6 had 95% CI bounds excluding 1.0 before but not after adjustment for multiple comparisons. Conclusion Our findings do not provide meaningful support for previously-posited associations between antihistamines and major congenital anomalies; at the same time, we identified associations that had not been previously suggested. We suspect that previous associations may be chance findings in the context of multiple comparisons, a situation which may also apply to our new findings. PMID:24565715

University Students' Strategies for Constructing Hypothesis when Tackling Paper-and-Pencil Tasks in Physics

NASA Astrophysics Data System (ADS)

Guisasola, Jenaro; Ceberio, Mikel; Zubimendi, José Luis

2006-09-01

The study we present tries to explore how first year engineering students formulate hypotheses in order to construct their own problem solving structure when confronted with problems in physics. Under the constructivistic perspective of the teaching-learning process, the formulation of hypotheses plays a key role in contrasting the coherence of the students' ideas with the theoretical frame. The main research instrument used to identify students' reasoning is the written report by the student on how they have attempted four problem solving tasks in which they have been asked explicitly to formulate hypotheses. The protocols used in the assessment of the solutions consisted of a semi-quantitative study based on grids designed for the analysis of written answers. In this paper we have included two of the tasks used and the corresponding scheme for the categorisation of the answers. Details of the other two tasks are also outlined. According to our findings we would say that the majority of students judge a hypothesis to be plausible if it is congruent with their previous knowledge without rigorously checking it against the theoretical framework explained in class.

Effects of olfactory sense on chocolate craving.

PubMed

Firmin, Michael W; Gillette, Aubrey L; Hobbs, Taylor E; Wu, Di

2016-10-01

In the present study, we assessed the effect of the olfactory sense on chocolate craving in college females. Building on previous research by Kemps and Tiggemann (2013), we hypothesized that a fresh scent would decrease one's craving level for chocolate food. While the precursor study only addressed the decrease of chocolate craving, we also hypothesized that a sweet scent would increase one's craving level for chocolate foods. In the present experiment, participants rated their craving levels after viewing images of chocolate foods and inhaling essential oils: one fresh (Slique™ essence), and one sweet (vanilla). Results supported both of the hypotheses: inhaling a fresh scent reduced females' craving levels; similarly, when a sweet scent was inhaled, the participants' craving levels for chocolate food increased. These findings are particularly beneficial for women seeking weight loss and the findings can be applied in contexts such as weight loss programs, therapy, and maintenance programs, even beyond college settings. The results are particularly useful for helping women regarding stimuli that might serve as triggers for chocolate cravings. Copyright © 2016 Elsevier Ltd. All rights reserved.

Interrelationships of Heterozygosity, Growth Rate and Heterozygote Deficiencies in the Coot Clam, Mulinia Lateralis

PubMed Central

Gaffney, P. M.; Scott, T. M.; Koehn, R. K.; Diehl, W. J.

1990-01-01

Allozyme surveys of marine invertebrates commonly report heterozygote deficiencies, a correlation between multiple locus heterozygosity and size, or both. Hypotheses advanced to account for these phenomena include inbreeding, null alleles, selection, spatial or temporal Wahlund effects, aneuploidy and molecular imprinting. Previous studies have been unable to clearly distinguish among these alternative hypotheses. This report analyzes a large data set (1906 individuals, 15 allozyme loci) from a single field collection of the coot clam Mulinia lateralis and demonstrates (1) significant heterozygote deficiencies at 13 of 15 loci, (2) a correlation between the magnitude of heterozygote deficiency at a locus and the effect of heterozygosity at that locus on shell length, and (3) a distribution of multilocus heterozygosity which deviates from that predicted by observed single-locus heterozygosities. A critical examination of the abovementioned hypotheses as sources of these findings rules out inbreeding, null alleles, aneuploidy, population mixing and imprinting as sole causes. The pooling of larval subpopulations subjected to varying degrees of selection, aneuploidy or imprinting could account for the patterns observed in this study. PMID:2311919

Using computational fluid dynamics to test functional and ecological hypotheses in fossil taxa

NASA Astrophysics Data System (ADS)

Rahman, Imran

2016-04-01

Reconstructing how ancient organisms moved and fed is a major focus of study in palaeontology. Traditionally, this has been hampered by a lack of objective data on the functional morphology of extinct species, especially those without a clear modern analogue. However, cutting-edge techniques for characterizing specimens digitally and in three dimensions, coupled with state-of-the-art computer models, now provide a robust framework for testing functional and ecological hypotheses even in problematic fossil taxa. One such approach is computational fluid dynamics (CFD), a method for simulating fluid flows around objects that has primarily been applied to complex engineering-design problems. Here, I will present three case studies of CFD applied to fossil taxa, spanning a range of specimen sizes, taxonomic groups and geological ages. First, I will show how CFD enabled a rigorous test of hypothesized feeding modes in an enigmatic Ediacaran organism with three-fold symmetry, revealing previously unappreciated complexity of pre-Cambrian ecosystems. Second, I will show how CFD was used to evaluate hydrodynamic performance and feeding in Cambrian stem-group echinoderms, shedding light on the probable feeding strategy of the latest common ancestor of all deuterostomes. Third, I will show how CFD allowed us to explore the link between form and function in Mesozoic ichthyosaurs. These case studies serve to demonstrate the enormous potential of CFD for addressing long-standing hypotheses for a variety of fossil taxa, opening up an exciting new avenue in palaeontological studies of functional morphology.

Cancer Risks near Nuclear Facilities: The Importance of Research Design and Explicit Study Hypotheses

PubMed Central

Wing, Steve; Richardson, David B.; Hoffmann, Wolfgang

2011-01-01

Background In April 2010, the U.S. Nuclear Regulatory Commission asked the National Academy of Sciences to update a 1990 study of cancer risks near nuclear facilities. Prior research on this topic has suffered from problems in hypothesis formulation and research design. Objectives We review epidemiologic principles used in studies of generic exposure–response associations and in studies of specific sources of exposure. We then describe logical problems with assumptions, formation of testable hypotheses, and interpretation of evidence in previous research on cancer risks near nuclear facilities. Discussion Advancement of knowledge about cancer risks near nuclear facilities depends on testing specific hypotheses grounded in physical and biological mechanisms of exposure and susceptibility while considering sample size and ability to adequately quantify exposure, ascertain cancer cases, and evaluate plausible confounders. Conclusions Next steps in advancing knowledge about cancer risks near nuclear facilities require studies of childhood cancer incidence, focus on in utero and early childhood exposures, use of specific geographic information, and consideration of pathways for transport and uptake of radionuclides. Studies of cancer mortality among adults, cancers with long latencies, large geographic zones, and populations that reside at large distances from nuclear facilities are better suited for public relations than for scientific purposes. PMID:21147606

Understanding the elevated suicide risk of female soldiers during deployments.

PubMed

Street, A E; Gilman, S E; Rosellini, A J; Stein, M B; Bromet, E J; Cox, K L; Colpe, L J; Fullerton, C S; Gruber, M J; Heeringa, S G; Lewandowski-Romps, L; Little, R J A; Naifeh, J A; Nock, M K; Sampson, N A; Schoenbaum, M; Ursano, R J; Zaslavsky, A M; Kessler, R C

2015-03-01

The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) has found that the proportional elevation in the US Army enlisted soldier suicide rate during deployment (compared with the never-deployed or previously deployed) is significantly higher among women than men, raising the possibility of gender differences in the adverse psychological effects of deployment. Person-month survival models based on a consolidated administrative database for active duty enlisted Regular Army soldiers in 2004-2009 (n = 975,057) were used to characterize the gender × deployment interaction predicting suicide. Four explanatory hypotheses were explored involving the proportion of females in each soldier's occupation, the proportion of same-gender soldiers in each soldier's unit, whether the soldier reported sexual assault victimization in the previous 12 months, and the soldier's pre-deployment history of treated mental/behavioral disorders. The suicide rate of currently deployed women (14.0/100,000 person-years) was 3.1-3.5 times the rates of other (i.e. never-deployed/previously deployed) women. The suicide rate of currently deployed men (22.6/100,000 person-years) was 0.9-1.2 times the rates of other men. The adjusted (for time trends, sociodemographics, and Army career variables) female:male odds ratio comparing the suicide rates of currently deployed v. other women v. men was 2.8 (95% confidence interval 1.1-6.8), became 2.4 after excluding soldiers with Direct Combat Arms occupations, and remained elevated (in the range 1.9-2.8) after adjusting for the hypothesized explanatory variables. These results are valuable in excluding otherwise plausible hypotheses for the elevated suicide rate of deployed women and point to the importance of expanding future research on the psychological challenges of deployment for women.

Cows with follicular fluid androgen excess exhibit anovulation and have altered circulating sex hormone binding globulin, gonadotropin secretion and plasma and follicular fluid composition

USDA-ARS?s Scientific Manuscript database

Our laboratory identified a group of cows with excess intrafollicular concentrations of androstenedione (A4; >30 fold), reduced calving rates, and theca gene expression profiles similar to women with Polycystic Ovary Syndrome (PCOS). Based on these previous studies, we hypothesized that High A4 cows...

The herb community of a tropical forest in central Panama: dynamics and impact of mammalian herbivores

Treesearch

Alejandro A. Royo; Walter P. Carson

2005-01-01

Mammals are hypothesized to either promote plant diversity by preventing competitive exclusion or limit diversity by reducing the abundance of sensitive plant species through their activities as browsers or disturbance agents. Previous studies of herbivore impacts in plant communities have focused on tree species and ignored the herbaceous community. In an experiment...

Syntactic Reflexes of Emerging Optionality in Spanish as a Heritage Language: The Case of Dative-Experiencer Verbs

ERIC Educational Resources Information Center

Pascual y Cabo, Diego

2016-01-01

This study contributes to current trends of heritage speaker bilingualism research by examining the syntax of so-called Spanish dative-experiencer predicates ("gustar"-like verbs). Building on previous findings (e.g., Silva-Corvalán 1994; Toribio and Nye 2006), it is hypothesized that Spanish heritage speakers can project an optional…

Investigation of possible causes for human-performance degradation during microgravity flight

NASA Technical Reports Server (NTRS)

Schroeder, James E.; Tuttle, Megan L.

1992-01-01

The results of the first year of a three year study of the effects of microgravity on human performance are given. Test results show support for the hypothesis that the effects of microgravity can be studied indirectly on Earth by measuring performance in an altered gravitational field. The hypothesis was that an altered gravitational field could disrupt performance on previously automated behaviors if gravity was a critical part of the stimulus complex controlling those behaviors. In addition, it was proposed that performance on secondary cognitive tasks would also degrade, especially if the subject was provided feedback about degradation on the previously automated task. In the initial experimental test of these hypotheses, there was little statistical support. However, when subjects were categorized as high or low in automated behavior, results for the former group supported the hypotheses. The predicted interaction between body orientation and level of workload in their joint effect on performance in the secondary cognitive task was significant for the group high in automatized behavior and receiving feedback, but no such interventions were found for the group high in automatized behavior but not receiving feedback, or the group low in automatized behavior.

Racial differences in sexual prejudice and its correlates among heterosexual men.

PubMed

Daboin, Irene; Peterson, John L; Parrott, Dominic J

2015-04-01

Previous research has consistently found sexual prejudice to be a predictor of antigay aggression and has also revealed specific correlates and antecedents of sexual prejudice. However, extant literature reveals mixed findings about potential racial group differences in sexual prejudice, and few studies have examined racial differences in the correlates of sexual prejudice. The aims of this descriptive study were to determine whether there are (a) racial group differences in reports of sexual prejudice and (b) racial group differences in previously identified correlates of sexual prejudice. Participants were 195 heterosexual males, ages 18 to 30 (98 Blacks and 97 Whites), recruited from a large metropolitan city in the southeastern United States. Based on cultural differences in the influence of religion and in attitudes about male sexuality, it was hypothesized that Black participants would report higher sexual prejudice than White participants. Additionally, based on cultural differences in racial views on masculinity and in sociocultural experiences of male gender roles, it was hypothesized that Blacks would report greater endorsement of religious fundamentalism and the traditional male role norm of status than Whites. Results confirmed all of the hypothesized racial differences and revealed additional differences, including a differential effect of the traditional male role norm of status on sexual prejudice, which explains, at least in part, the racial differences found in sexual prejudice. These findings may reflect underlying cultural differences between Black and White males and may aid in the development of future efforts to reduce sexual prejudice and consequently antigay aggression toward sexual minorities. (c) 2015 APA, all rights reserved).

The Trans-Contextual Model of Autonomous Motivation in Education

PubMed Central

Hagger, Martin S.; Chatzisarantis, Nikos L. D.

2015-01-01

The trans-contextual model outlines the processes by which autonomous motivation toward activities in a physical education context predicts autonomous motivation toward physical activity outside of school, and beliefs about, intentions toward, and actual engagement in, out-of-school physical activity. In the present article, we clarify the fundamental propositions of the model and resolve some outstanding conceptual issues, including its generalizability across multiple educational domains, criteria for its rejection or failed replication, the role of belief-based antecedents of intentions, and the causal ordering of its constructs. We also evaluate the consistency of model relationships in previous tests of the model using path-analytic meta-analysis. The analysis supported model hypotheses but identified substantial heterogeneity in the hypothesized relationships across studies unattributed to sampling and measurement error. Based on our meta-analysis, future research needs to provide further replications of the model in diverse educational settings beyond physical education and test model hypotheses using experimental methods. PMID:27274585

The Trans-Contextual Model of Autonomous Motivation in Education: Conceptual and Empirical Issues and Meta-Analysis.

PubMed

Hagger, Martin S; Chatzisarantis, Nikos L D

2016-06-01

The trans-contextual model outlines the processes by which autonomous motivation toward activities in a physical education context predicts autonomous motivation toward physical activity outside of school, and beliefs about, intentions toward, and actual engagement in, out-of-school physical activity. In the present article, we clarify the fundamental propositions of the model and resolve some outstanding conceptual issues, including its generalizability across multiple educational domains, criteria for its rejection or failed replication, the role of belief-based antecedents of intentions, and the causal ordering of its constructs. We also evaluate the consistency of model relationships in previous tests of the model using path-analytic meta-analysis. The analysis supported model hypotheses but identified substantial heterogeneity in the hypothesized relationships across studies unattributed to sampling and measurement error. Based on our meta-analysis, future research needs to provide further replications of the model in diverse educational settings beyond physical education and test model hypotheses using experimental methods.

Do family order and neighbor intervention against intimate partner violence protect children from abuse? Findings from Kathmandu.

PubMed

Emery, Clifton R; Thapa, Sirjana; Do, Mi Hyang; Chan, Ko Ling

2015-03-01

Drawing on previous research on intimate partner violence, child maltreatment, and informal social control, we hypothesized relationships between child abuse severity and (1) protective informal social control of intimate partner violence (ISC_IPV) by neighbors, (2) intimate terrorism, (3) family order, and (4) the power of mothers in intimate relationships. In what we believe may be a first study of physical child abuse by parents in Nepal, we used a three stage cluster approach to draw a random sample of 300 families in Kathmandu. Random effects regression models were used to test the study hypotheses. The analyses found support for hypotheses one and two, but with an important caveat. Although observed (actual) protective ISC_IPV had the hypothesized negative association with child abuse severity, in one of our models perceived protective ISC_IPV was positively associated with child abuse severity. The models clarify that the overall direction of protective ISC_IPV appears to be negative (protective), but the positive finding is important to consider for both research and practice. A significant relationship between family order and child abuse severity was found, but the direction was negative rather than positive as in hypothesis three. Implications for neighborhood research and typological research on IPV and child maltreatment are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

Monogamy in marine fishes.

PubMed

Whiteman, E A; Côte, I M

2004-05-01

The formation of long-term pair bonds in marine fish has elicited much empirical study. However, the evolutionary mechanisms involved remain contested and previous theoretical frameworks developed to explain monogamy in birds and mammals are not applicable to many cases of monogamy in marine fish. In this review, we summarise all reported occurrences of social monogamy in marine fish, which has so far been observed in 18 fish families. We test quantitatively the role of ecological and behavioural traits previously suggested to be important for the evolution of monogamy and show that monogamous species occur primarily in the tropics and are associated with coral reef environments in which territory defence and site attachment is facilitated. However, there is little evidence that obligately monogamous species are smaller in body size than species that can adopt a polygynous mating system. We review the evidence pertaining to six hypotheses suggested for the evolution of monogamous pair bonds: (1) biparental care, (2) habitat limitation, (3) low population density/low mate availability/low mobility, (4) increased reproductive efficiency, (5) territory defence, and (6) net benefit of single mate sequestration. We outline predictions and associated empirical tests that can distinguish between these hypotheses, and assess how generally each hypothesis explains monogamy within and between breeding periods for species with different types of territories (i.e. feeding only or feeding and breeding). Hypotheses (1) and (2) have limited applicability to marine fishes, while hypotheses (3)-(5) have little empirical support beyond the species for which they were designed. However, the role of paternal care in promoting monogamous pair bonds is not explicit in these hypotheses, yet paternal care has been reported in more than 70 monogamous marine fish. We show that paternal care may act to increase the likelihood of monogamy in combination with each of the proposed hypotheses through decreased benefits to males from searching for additional mates or increased advantages to females from sequestering a single high-quality mate. Among species defending breeding and feeding territories, the benefits, both within and between reproductive periods, of sequestering a single high-quality mate (hypothesis 6) appear to be the best explanation for socially monogamous pairs. For species without parental care (i.e. holding only feeding territories), territory defence (hypothesis 5) in combination with the benefits of guarding a large mate (hypothesis 6) could potentially explain most instances of monogamy. Empirical studies of marine fishes over the past two decades are therefore slowly changing the view of monogamy from a mating system imposed upon species by environmental constraints to one with direct benefits to both sexes.

Probability Matching in the Right Hemisphere

ERIC Educational Resources Information Center

Miller, M.B.; Valsangkar-Smyth, M.

2005-01-01

Previously it has been shown that the left hemisphere, but not the right, of split-brain patients tends to match the frequency of previous occurrences in probability-guessing paradigms (Wolford, Miller, & Gazzaniga, 2000). This phenomenon has been attributed to an ''interpreter,'' a mechanism for making interpretations and forming hypotheses,…

Motor Anticipation Failure in Infants with Autism: A Retrospective Analysis of Feeding Situations

ERIC Educational Resources Information Center

Brisson, Julie; Warreyn, Petra; Serres, Josette; Foussier, Stephane; Adrien-Louis, Jean

2012-01-01

Previous studies on autism have shown a lack of motor anticipation in children and adults with autism. As part of a programme of research into early detection of autism, we focussed on an everyday situation: spoon-feeding. We hypothesize that an anticipation deficit may be found very early on by observing whether the baby opens his or her mouth in…

Does a "Norm of Self-Interest" Discourage Prosocial Behavior? Rationality and Quid Pro Quo in Charitable Giving

ERIC Educational Resources Information Center

Simpson, Brent; Irwin, Kyle; Lawrence, Peter

2006-01-01

Previous studies by Holmes, Miller, and Lerner (2002) support the norm of self-interest and exchange fiction hypotheses. Together these arguments state that people want to act on compassionate feelings (e.g., by donating to charities) but are reluctant to do so if they cannot justify their behavior as being in line with their own self-interest.…

Deterrence Theory and the Role of Shame in Projected Offending of College Students against a Ban on Alcohol

ERIC Educational Resources Information Center

Kelley, Margaret S.; Fukushima, Miyuki; Spivak, Andrew L.; Payne, David

2009-01-01

In the present study we advance previous research in deterrence theory by examining the perceived deterrent effects of a newly instituted dry policy on a college campus. A survey of 500 full-time undergraduate students between the ages of 18 and 26 was conducted 3 months following the ban on alcohol. Hypotheses are derived from deterrence theory…

The Impact of Malnutrition on Intelligence at 3 and 11 Years of Age: The Mediating Role of Temperament

ERIC Educational Resources Information Center

Venables, Peter H.; Raine, Adrian

2016-01-01

Previous work has shown that malnutrition has deleterious effects on both IQ and aspects of temperament. It is hypothesized that while malnutrition bears a direct relation to IQ, aspects of temperament are also involved in a mediating role so that they produce indirect associations between malnutrition and IQ. The study examines the association of…

Factors controlling plasticity of leaf morphology in Robinia pseudoacacia L. II: the impact of water stress on leaf morphology of seedlings grown in a controlled environment chamber

Treesearch

M.T. Tyree

2012-01-01

Context. The cause of morphological plasticity of leaves within the crowns of tall trees still debated. Whether it is driven by irradiance or hydraulic constraints is inconclusive. In a previous study, we hypothesized that water stress caused between-site and within-tree morphological variability in mature Robinia trees.

Determining the effects of early gestation in utero heat stress on postnatal fasting heat production and circulating biomarkers associated with metabolism in growing pigs

USDA-ARS?s Scientific Manuscript database

The study objective was to determine the effects of in utero heat stress (IUHS) on postnatal fasting heat production (FHP) in growing pigs. Based on our previous observation of increased postnatal core body temperature ‘set-point’ in IUHS pigs, we hypothesized that FHP would be greater during postna...

Thinking strategies used by Registered Nurses during emergency department triage.

PubMed

Göransson, Katarina E; Ehnfors, Margareta; Fonteyn, Marsha E; Ehrenberg, Anna

2008-01-01

This paper is a report of a study to describe and compare thinking strategies and cognitive processing in the emergency department triage process by Registered Nurses with high and low triage accuracy. Sound clinical reasoning and accurate decision-making are integral parts of modern nursing practice and are of vital importance during triage in emergency departments. Although studies have shown that individual and contextual factors influence the decisions of Registered Nurses in the triage process, others have failed to explain the relationship between triage accuracy and clinical experience. Furthermore, no study has shown the relationship between Registered Nurses' thinking strategies and their triage accuracy. Using the 'think aloud' method, data were collected in 2004-2005 from 16 RNs working in Swedish emergency departments who had previously participated in a study examining triage accuracy. Content analysis of the data was performed. The Registered Nurses used a variety of thinking strategies, ranging from searching for information, generating hypotheses to stating propositions. They structured the triage process in several ways, beginning by gathering data, generating hypotheses or allocating acuity ratings. Comparison of participants' use of thinking strategies and the structure of the triage process based on their previous triage accuracy revealed only slight differences. The wide range of thinking strategies used by Registered Nurses when performing triage indicates that triage decision-making is complex. Further research is needed to ascertain which skills are most important in triage decision-making.

Working memory effects of gap-predictions in normal adults: an event-related potentials study.

PubMed

Hestvik, Arild; Bradley, Evan; Bradley, Catherine

2012-12-01

The current study examined the relationship between verbal memory span and the latency with which a filler-gap dependency is constructed. A previous behavioral study found that low span listeners did not exhibit antecedent reactivation at gap sites in relative clauses, in comparison to high verbal memory span subjects (Roberts et al. in J Psycholinguist Res 36(2):175-188, 2007), which suggests that low span subjects are delayed at gap filling. This possibility was examined in the current study. Using an event-related potentials paradigm, it was found that low span subjects have an onset latency delay of about 200 ms in brain responses to violations of syntactic expectancies after the gap site, thus providing a time course measure of the delay hypothesized by previous literature.

Sleep Paralysis Among Egyptian College Students: Association With Anxiety Symptoms (PTSD, Trait Anxiety, Pathological Worry).

PubMed

Jalal, Baland; Hinton, Devon E

2015-11-01

Among Egyptian college students in Cairo (n = 100), this study examined the relationship between sleep paralysis (SP) and anxiety symptoms, viz., posttraumatic stress disorder (PTSD), trait anxiety, and pathological worry. SP rates were high; 43% of participants reported at least one lifetime episode of SP, and 24% of those who reported at least one lifetime episode had experienced four or more episodes during the previous year. Fourteen percent of men had experienced SP as compared to 86% of women. As hypothesized, relative to non-SP experiencers, participants who had SP reported higher symptoms of PTSD, trait anxiety, and pathological worry. Also, as hypothesized, the experiencing of hypnogogic/hypnopompic hallucinations during SP, even after controlling for negative affect, was highly correlated with symptoms of PTSD and trait anxiety. The study also investigated possible mechanisms by examining the relationship of hallucinations to anxiety variables.

Assaults on Inmates and Staff by Perpetrators of Intimate Partner Homicide: An Examination of Competing Hypotheses.

PubMed

Sorensen, Jonathan R; Vigen, Mark P; Woods, S O; Williams, Bradley D

2015-11-01

The current study presents the results of an analysis of serious and assaultive prison rule violating behavior among male perpetrators of intimate partner homicide (IPH). Data on prison rule violations were collected from a sample of 189 inmates convicted of IPH in a large, southern prison system. The study focused on the degree of continuity in violent behavior among IPH offenders from the community to the prison setting. The current study tested hypotheses derived from both the feminist perspective (FP) and the general violence perspective (GVP). As a group, IPH offenders were better behaved in prison than other incarcerated homicide offenders, thereby offering some support for the FP. However, the lower level of assaultive behavior among the group was not universal. Characteristics associated with continued violent offending in the prison environment were the same as those found in previous studies of incarcerated homicide offenders, thereby lending greater support to the GVP. © The Author(s) 2014.

Molecular phylogeny of microhylid frogs (Anura: Microhylidae) with emphasis on relationships among New World genera

PubMed Central

2012-01-01

Background Over the last ten years we have seen great efforts focused on revising amphibian systematics. Phylogenetic reconstructions derived from DNA sequence data have played a central role in these revisionary studies but have typically under-sampled the diverse frog family Microhylidae. Here, we present a detailed phylogenetic study focused on expanding previous hypotheses of relationships within this cosmopolitan family. Specifically, we placed an emphasis on assessing relationships among New World genera and those taxa with uncertain phylogenetic affinities (i.e., incertae sedis). Results One mitochondrial and three nuclear genes (about 2.8 kb) were sequenced to assess phylogenetic relationships. We utilized an unprecedented sampling of 200 microhylid taxa representing 91% of currently recognized subfamilies and 95% of New World genera. Our analyses do not fully resolve relationships among subfamilies supporting previous studies that have suggested a rapid early diversification of this clade. We observed a close relationship between Synapturanus and Otophryne of the subfamily Otophryninae. Within the subfamily Gastrophryninae relationships between genera were well resolved. Conclusion Otophryninae is distantly related to all other New World microhylids that were recovered as a monophyletic group, Gastrophryninae. Within Gastrophryninae, five genera were recovered as non-monophyletic; we propose taxonomic re-arrangements to render all genera monophyletic. This hypothesis of relationships and updated classification for New World microhylids may serve as a guide to better understand the evolutionary history of this group that is apparently subject to convergent morphological evolution and chromosome reduction. Based on a divergence analysis calibrated with hypotheses from previous studies and fossil data, it appears that microhylid genera inhabiting the New World originated during a period of gradual cooling from the late Oligocene to mid Miocene. PMID:23228209

Head size, weaponry, and cervical adaptation: Testing craniocervical evolutionary hypotheses in Ceratopsia.

PubMed

VanBuren, Collin S; Campione, Nicolás E; Evans, David C

2015-07-01

The anterior cervical vertebrae form the skeletal connection between the cranial and postcranial skeletons in higher tetrapods. As a result, the morphology of the atlas-axis complex is likely to be shaped by selection pressures acting on either the head or neck. The neoceratopsian (Reptilia:Dinosauria) syncervical represents one of the most highly modified atlas-axis regions in vertebrates, being formed by the complete coalescence of the three most anterior cervical vertebrae. In ceratopsids, the syncervical has been hypothesized to be an adaptation to support a massive skull, or to act as a buttress during intraspecific head-to-head combat. Here, we test these functional/adaptive hypotheses within a phylogenetic framework and critically examine the previously proposed methods for quantifying relative head size in the fossil record for the first time. Results indicate that neither the evolution of cranial weaponry nor large head size correlates with the origin of cervical fusion in ceratopsians, and we, therefore, reject both adaptive hypotheses for the origin of the syncervical. Anterior cervical fusion has evolved independently in a number of amniote clades, and further research on extant groups with this peculiar anatomy is needed to understand the evolutionary basis for cervical fusion in Neoceratopsia. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Reducing self-objectification: are dissonance-based methods a possible approach?

PubMed

Becker, Carolyn Black; Hill, Kaitlin; Greif, Rebecca; Han, Hongmei; Stewart, Tiffany

2013-01-01

Previous research has documented that self-objectification is associated with numerous negative outcomes including body shame, eating disorder (ED) pathology, and negative affect. This exploratory open study investigated whether or not an evidence-based body image improvement program that targets thin-ideal internalization in university women also reduces self-objectification. A second aim of the study was to determine if previous findings showing that body shame mediated the relationship between self-objectification and eating disorder pathology at a single time point (consistent with self-objectification theory) but did not mediate longitudinally (inconsistent with self-objectification theory) would be replicated in a new sample under novel conditions. Ninety-six university women completed a peer-led dissonance-based intervention, along with assessment measures at pre-, post-intervention, 8-week and 8-month follow-up. To address the open trial nature of this study, a planned manipulation check was included to make sure that peer-led dissonance decreased thin-ideal internalization, body dissatisfaction, eating disorder pathology, and negative affect with effect sizes being similar to past randomized controlled trials. We hypothesized that all three subscales of the Objectified Body Consciousness Scale (i.e., self-surveillance, body shame, and appearance control beliefs) would be reduced. In addition, we hypothesized that body shame would mediate the relationship between self-objectification (i.e., self-surveillance) and eating disorder pathology at a both at a single time point and longitudinally. The planned manipulation check supported the interpretation that peer-led dissonance in this study largely yielded comparable changes to past controlled trials. In terms of changes in dependent variables, results supported all hypotheses with the exception of body shame, which remained unchanged. With regards to the mediation analyses, our first (cross-sectional) hypothesis but not our second (longitudinal) was supported. Findings provide preliminary support for the use of dissonance interventions in reducing self-surveillance and body control beliefs. Results for body shame and the mediation analyses suggest that greater scrutiny of the body shame construct is warranted.

It takes two to talk: a second-person neuroscience approach to language learning.

PubMed

Syal, Supriya; Anderson, Adam K

2013-08-01

Language is a social act. We have previously argued that language remains embedded in sociality because the motivation to communicate exists only within a social context. Schilbach et al. underscore the importance of studying linguistic behavior from within the motivated, socially interactive frame in which it is learnt and used, as well as provide testable hypotheses for a participatory, second-person neuroscience approach to language learning.

Does Being Assigned to a Low School Track Negatively Affect Psychological Adjustment? A Longitudinal Study in the First Year of Secondary School

ERIC Educational Resources Information Center

Müller, Christoph Michael; Hofmann, Verena

2016-01-01

Previous research suggests that the 1st year in secondary school for some students goes hand in hand with an increase in adjustment difficulties. One factor that might influence this process on an individual, compositional, and institutional level is the academic track a student attends. It was hypothesized that being assigned to a low-qualifying…

On the quest for a biomechanism of transsexualism: is there a role for BDNF?

PubMed

Fuss, Johannes; Biedermann, Sarah V; Stalla, Günter K; Auer, Matthias K

2013-12-01

Previous studies hypothesized a neurobiological mechanism for gender identity disorder (GID). Recently a possible role for serum brain-derived neurotrophic factor (BDNF) was suggested on the basis of reduced serum BDNF levels in male-to-female individuals. Here we review the question whether there is indeed a role of BDNF in the development of transsexualism. Copyright © 2013 Elsevier Ltd. All rights reserved.

Cumulative Causation, Market Transition, and Emigration from China

PubMed Central

Liang, Zai; Chunyu, Miao David; Zhuang, Guotu; Ye, Wenzhen

2009-01-01

In this paper, we report findings from a recent survey of international migration from China's Fujian province to the United States. We take advantage of the ethnosurvey approach as used in the Mexican Migration Project. Surveys were done in migrant-sending communities in China as well as in destination communities of New York City. We derive hypotheses from two strands of recent studies-the international migration literature and the market transition debate. Our results are in general consistent with hypotheses derived from cumulative causation of migration. However, because of the geographical location of China as compared to Mexico, there are some differences between the two countries in terms of particular migration patterns to the United States. As expected, at the community level, migration prevalence ratio (measuring migration networks) increases the propensity of migration for other members in the community. In contrast, having a household member migrated previously does not increase the propensity of migration of other household members until debt for previous migration is paid off. Our research clearly demonstrates the value of bringing the case of China into the comparative study of international migration. With respect to market transition theory, we find that political power continues to be an important factor in the order of social stratification in the coastal Fujian province. PMID:19569396

Development of a patient-reported outcome measure of recovery after abdominal surgery: a hypothesized conceptual framework.

PubMed

Alam, Roshni; Figueiredo, Sabrina M; Balvardi, Saba; Nauche, Bénédicte; Landry, Tara; Lee, Lawrence; Mayo, Nancy E; Feldman, Liane S; Fiore, Julio F

2018-05-17

We initiated a research program to develop a novel patient-reported outcome measure (PROM) to assess postoperative recovery from the perspective of abdominal surgery patients. In light of FDA recommendations, the first stage of our program aimed to, based on previous literature and expert input, develop a hypothesized conceptual framework portraying the health domains that are potentially relevant to the process of recovery after abdominal surgery. This study was conducted in three phases: (1) systematic review to identify PROMs with measurement properties appraised in the context of recovery after abdominal surgery, (2) content analysis to categorize the health domains covered by the PROMs according to the ICF, and (3) two-round Delphi study to gain expert input regarding which of these health domains are relevant to the process of recovery. Participants were experts in perioperative care identified through two major surgical societies (35 invited). The systematic review identified 19 PROMs covering 66 ICF domains. 23 experts (66%) participated in the Delphi process. After Round 2, experts agreed that 22 health domains (8 body functions, 14 activities and participation) are potentially relevant to the process of recovery after abdominal surgery. These domains were organized into a diagram, representing our hypothesized conceptual framework. This hypothesized conceptual framework is an important first step in our research program and will be further refined based on in-depth qualitative interviews with patients. The sound methodological approach used to derive this framework may be valuable for studies aimed to develop PROMs according to FDA standards.

Sexual and Emotional Infidelity: Evolved Gender Differences in Jealousy Prove Robust and Replicable.

PubMed

Buss, David M

2018-03-01

Infidelity poses threats to high-investment mating relationships. Because of gender differences in some aspects of reproductive biology, such as internal female fertilization, the nature of these threats differs for men and women. Men, but not women, for example, have recurrently faced the problem of uncertainty in their genetic parenthood. Jealousy is an emotion hypothesized to have evolved to combat these threats. The 1992 article Sex Differences in Jealousy: Evolution, Physiology, and Psychology reported three empirical studies using two different methods, forced-choice and physiological experiments. Results supported the evolution-based hypotheses. The article became highly cited for several reasons. It elevated the status of jealousy as an important emotion to be explained by any comprehensive theory of human emotions. Subsequent meta-analyses robustly supported the evolutionary hypotheses. Moreover, the work supported the evolutionary meta-theory of gender differences, which posits differences only in domains in which the sexes have recurrently faced distinct adaptive problems. It also heralded the newly emerging field of evolutionary psychology as a useful perspective that possesses the scientific virtues of testability, falsifiability, and heuristic value in discovering previously unknown psychological phenomena.

No evidence for bilingual cognitive advantages: A test of four hypotheses.

PubMed

von Bastian, Claudia C; Souza, Alessandra S; Gade, Miriam

2016-02-01

The question whether being bilingual yields cognitive benefits is highly controversial with prior studies providing inconsistent results. Failures to replicate the bilingual advantage have been attributed to methodological factors such as comparing dichotomous groups and measuring cognitive abilities separately with single tasks. Therefore, the authors evaluated the 4 most prominent hypotheses of bilingual advantages for inhibitory control, conflict monitoring, shifting, and general cognitive performance by assessing bilingualism on 3 continuous dimensions (age of acquisition, proficiency, and usage) in a sample of 118 young adults and relating it to 9 cognitive abilities each measured by multiple tasks. Linear mixed-effects models accounting for multiple sources of variance simultaneously and controlling for parents' education as an index of socioeconomic status revealed no evidence for any of the 4 hypotheses. Hence, the authors' results suggest that bilingual benefits are not as broad and as robust as has been previously claimed. Instead, earlier effects were possibly due to task-specific effects in selective and often small samples. PsycINFO Database Record (c) 2016 APA, all rights reserved.

Using a virtual reality temporal bone simulator to assess otolaryngology trainees.

PubMed

Zirkle, Molly; Roberson, David W; Leuwer, Rudolf; Dubrowski, Adam

2007-02-01

The objective of this study is to determine the feasibility of computerized evaluation of resident performance using hand motion analysis on a virtual reality temporal bone (VR TB) simulator. We hypothesized that both computerized analysis and expert ratings would discriminate the performance of novices from experienced trainees. We also hypothesized that performance on the virtual reality temporal bone simulator (VR TB) would differentiate based on previous drilling experience. The authors conducted a randomized, blind assessment study. Nineteen volunteers from the Otolaryngology-Head and Neck Surgery training program at the University of Toronto drilled both a cadaveric TB and a simulated VR TB. Expert reviewers were asked to assess operative readiness of the trainee based on a blind video review of their performance. Computerized hand motion analysis of each participant's performance was conducted. Expert raters were able to discriminate novices from experienced trainees (P < .05) on cadaveric temporal bones, and there was a trend toward discrimination on VR TB performance. Hand motion analysis showed that experienced trainees had better movement economy than novices (P < .05) on the VR TB. Performance, as measured by hand motion analysis on the VR TB simulator, reflects trainees' previous drilling experience. This study suggests that otolaryngology trainees could accomplish initial temporal bone training on a VR TB simulator, which can provide feedback to the trainee, and may reduce the need for constant faculty supervision and evaluation.

Testing Hypotheses on Risk Factors for Scientific Misconduct via Matched-Control Analysis of Papers Containing Problematic Image Duplications.

PubMed

Fanelli, Daniele; Costas, Rodrigo; Fang, Ferric C; Casadevall, Arturo; Bik, Elisabeth M

2018-02-19

It is commonly hypothesized that scientists are more likely to engage in data falsification and fabrication when they are subject to pressures to publish, when they are not restrained by forms of social control, when they work in countries lacking policies to tackle scientific misconduct, and when they are male. Evidence to test these hypotheses, however, is inconclusive due to the difficulties of obtaining unbiased data. Here we report a pre-registered test of these four hypotheses, conducted on papers that were identified in a previous study as containing problematic image duplications through a systematic screening of the journal PLoS ONE. Image duplications were classified into three categories based on their complexity, with category 1 being most likely to reflect unintentional error and category 3 being most likely to reflect intentional fabrication. We tested multiple parameters connected to the hypotheses above with a matched-control paradigm, by collecting two controls for each paper containing duplications. Category 1 duplications were mostly not associated with any of the parameters tested, as was predicted based on the assumption that these duplications were mostly not due to misconduct. Categories 2 and 3, however, exhibited numerous statistically significant associations. Results of univariable and multivariable analyses support the hypotheses that academic culture, peer control, cash-based publication incentives and national misconduct policies might affect scientific integrity. No clear support was found for the "pressures to publish" hypothesis. Female authors were found to be equally likely to publish duplicated images compared to males. Country-level parameters generally exhibited stronger effects than individual-level parameters, because developing countries were significantly more likely to produce problematic image duplications. This suggests that promoting good research practices in all countries should be a priority for the international research integrity agenda.

Oxytocin, vasopressin, and autism: is there a connection?

PubMed

Insel, T R; O'Brien, D J; Leckman, J F

1999-01-15

Autism is a poorly understood developmental disorder characterized by social impairment, communication deficits, and compulsive behavior. The authors review evidence from animal studies demonstrating that the nonapeptides, oxytocin and vasopressin, have unique effects on the normal expression of species-typical social behavior, communication, and rituals. Based on this evidence, they hypothesize that an abnormality in oxytocin or vasopressin neurotransmission may account for several features of autism. As autism appears to be a genetic disorder, mutations in the various peptide, peptide receptor, or lineage-specific developmental genes could lead to altered oxytocin or vasopressin neurotransmission. Many of these genes have been cloned and sequenced, and several polymorphisms have been identified. Recent gene targeting studies that alter expression of either the peptides or their receptors in the rodent brain partially support the autism hypothesis. While previous experience suggests caution in hypothesizing a cause or suggesting a treatment for autism, the available preclinical evidence with oxytocin and vasopressin recommends the need for clinical studies using gene scanning, pharmacological and neurobiological approaches.

Effects of everyday romantic goal pursuit on women's attitudes toward math and science.

PubMed

Park, Lora E; Young, Ariana F; Troisi, Jordan D; Pinkus, Rebecca T

2011-09-01

The present research examined the impact of everyday romantic goal strivings on women's attitudes toward science, technology, engineering, and math (STEM). It was hypothesized that women may distance themselves from STEM when the goal to be romantically desirable is activated because pursuing intelligence goals in masculine domains (i.e., STEM) conflicts with pursuing romantic goals associated with traditional romantic scripts and gender norms. Consistent with hypotheses, women, but not men, who viewed images (Study 1) or overheard conversations (Studies 2a-2b) related to romantic goals reported less positive attitudes toward STEM and less preference for majoring in math/science compared to other disciplines. On days when women pursued romantic goals, the more romantic activities they engaged in and the more desirable they felt, but the fewer math activities they engaged in. Furthermore, women's previous day romantic goal strivings predicted feeling more desirable but being less invested in math on the following day (Study 3).

Disgust and Obsessive Beliefs in Contamination-related OCD

PubMed Central

Cisler, Josh M.; Brady, Robert E.; Olatunji, Bunmi O.; Lohr, Jeffrey M.

2010-01-01

A large body of evidence suggests that disgust is an important affective process underlying contamination fear. An independent line of research demonstrates that obsessive beliefs, particularly overestimations of threat, are also an important cognitive process underlying contamination fear. The present study attempts to integrate these two lines of research by testing whether obsessive beliefs potentiate the influence of disgust propensity on contamination fear. The interaction between disgust propensity and obsessive beliefs was tested in two large non-clinical samples (N = 252 in Study 1; N = 308 in Study 2) using two different self-report measures of contamination fear. Regression analyses supported the hypotheses in both samples. The interaction remained significant when controlling for negative affect. The results are hypothesized to suggest that contamination fear results, at least partly, from obsessive beliefs about the contamination-based appraisals that accompany heightened disgust responding. These results complement previous affective-driven explanations of the role of disgust in contamination fear by suggesting cognitive factors that similarly potentiate disgust’s role in contamination fear. PMID:20877585

Understanding the elevated suicide risk of female soldiers during deployments

PubMed Central

Street, A. E.; Gilman, S. E.; Rosellini, A. J.; Stein, M. B.; Bromet, E. J.; Cox, K. L.; Colpe, L. J.; Fullerton, C. S.; Gruber, M. J.; Heeringa, S. G.; Lewandowski-Romps, L.; Little, R. J. A.; Naifeh, J. A.; Nock, M. K.; Sampson, N. A.; Schoenbaum, M.; Ursano, R. J.; Zaslavsky, A. M.; Kessler, R. C.

2016-01-01

Background The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) has found that the proportional elevation in the US Army enlisted soldier suicide rate during deployment (compared with the never-deployed or previously deployed) is significantly higher among women than men, raising the possibility of gender differences in the adverse psychological effects of deployment. Method Person-month survival models based on a consolidated administrative database for active duty enlisted Regular Army soldiers in 2004–2009 (n = 975 057) were used to characterize the gender × deployment interaction predicting suicide. Four explanatory hypotheses were explored involving the proportion of females in each soldier’s occupation, the proportion of same-gender soldiers in each soldier’s unit, whether the soldier reported sexual assault victimization in the previous 12 months, and the soldier’s pre-deployment history of treated mental/behavioral disorders. Results The suicide rate of currently deployed women (14.0/100 000 person-years) was 3.1–3.5 times the rates of other (i.e. never-deployed/previously deployed) women. The suicide rate of currently deployed men (22.6/100 000 person-years) was 0.9–1.2 times the rates of other men. The adjusted (for time trends, sociodemographics, and Army career variables) female:male odds ratio comparing the suicide rates of currently deployed v. other women v. men was 2.8 (95% confidence interval 1.1–6.8), became 2.4 after excluding soldiers with Direct Combat Arms occupations, and remained elevated (in the range 1.9–2.8) after adjusting for the hypothesized explanatory variables. Conclusions These results are valuable in excluding otherwise plausible hypotheses for the elevated suicide rate of deployed women and point to the importance of expanding future research on the psychological challenges of deployment for women. PMID:25359554

The role of Patient Health Engagement Model (PHE-model) in affecting patient activation and medication adherence: A structural equation model

PubMed Central

Graffigna, Guendalina; Bonanomi, Andrea

2017-01-01

Background Increasing bodies of scientific research today examines the factors and interventions affecting patients’ ability to self-manage and adhere to treatment. Patient activation is considered the most reliable indicator of patients’ ability to manage health autonomously. Only a few studies have tried to assess the role of psychosocial factors in promoting patient activation. A more systematic modeling of the psychosocial factors explaining the variance of patient activation is needed. Objective To test the hypothesized effect of patient activation on medication adherence; to test the the hypothesized effects of positive emotions and of the quality of the patient/doctor relationship on patient activation; and to test the hypothesized mediating effect of Patient Health Engagement (PHE-model) in this pathway. Material and methods This cross-sectional study involved 352 Italian-speaking adult chronic patients. The survey included measures of i) patient activation (Patient Activation Measure 13 –short form); ii) Patient Health Engagement model (Patient Health Engagement Scale); iii) patient adherence (4 item-Morinsky Medication Adherence Scale); iv) the quality of the patients’ emotional feelings (Manikin Self Assessment Scale); v) the quality of the patient/doctor relationship (Health Care Climate Questionnaire). Structural equation modeling was used to test the hypotheses proposed. Results According to the theoretical model we hypothesized, research results confirmed that patients’ activation significantly affects their reported medication adherence. Moreover, psychosocial factors, such as the patients’ quality of the emotional feelings and the quality of the patient/doctor relationship were demonstrated to be factors affecting the level of patient activation. Finally, the mediation effect of the Patient Health Engagement model was confirmed by the analysis. Conclusions Consistently with the results of previous studies, these findings demonstrate that the Patient Health Engagement Model is a critical factor in enhancing the quality of care. The Patient Health Engagement Model might acts as a mechanism to increase patient activation and adherence. PMID:28654686

The role of Patient Health Engagement Model (PHE-model) in affecting patient activation and medication adherence: A structural equation model.

PubMed

Graffigna, Guendalina; Barello, Serena; Bonanomi, Andrea

2017-01-01

Increasing bodies of scientific research today examines the factors and interventions affecting patients' ability to self-manage and adhere to treatment. Patient activation is considered the most reliable indicator of patients' ability to manage health autonomously. Only a few studies have tried to assess the role of psychosocial factors in promoting patient activation. A more systematic modeling of the psychosocial factors explaining the variance of patient activation is needed. To test the hypothesized effect of patient activation on medication adherence; to test the the hypothesized effects of positive emotions and of the quality of the patient/doctor relationship on patient activation; and to test the hypothesized mediating effect of Patient Health Engagement (PHE-model) in this pathway. This cross-sectional study involved 352 Italian-speaking adult chronic patients. The survey included measures of i) patient activation (Patient Activation Measure 13 -short form); ii) Patient Health Engagement model (Patient Health Engagement Scale); iii) patient adherence (4 item-Morinsky Medication Adherence Scale); iv) the quality of the patients' emotional feelings (Manikin Self Assessment Scale); v) the quality of the patient/doctor relationship (Health Care Climate Questionnaire). Structural equation modeling was used to test the hypotheses proposed. According to the theoretical model we hypothesized, research results confirmed that patients' activation significantly affects their reported medication adherence. Moreover, psychosocial factors, such as the patients' quality of the emotional feelings and the quality of the patient/doctor relationship were demonstrated to be factors affecting the level of patient activation. Finally, the mediation effect of the Patient Health Engagement model was confirmed by the analysis. Consistently with the results of previous studies, these findings demonstrate that the Patient Health Engagement Model is a critical factor in enhancing the quality of care. The Patient Health Engagement Model might acts as a mechanism to increase patient activation and adherence.

Domain Cell Theory supports the independent evolution of the Eukarya, Bacteria and Archaea and the Nuclear Compartment Commonality hypothesis.

PubMed

Staley, James T

2017-06-01

In 2015, the Royal Society of London held a meeting to discuss the various hypotheses regarding the origin of the Eukarya. Although not all participants supported a hypothesis, the proposals that did fit into two broad categories: one group favoured 'Prokaryotes First' hypotheses and another addressed 'Eukaryotes First' hypotheses. Those who proposed Prokaryotes First hypotheses advocated either a fusion event between a bacterium and an archaeon that produced the first eukaryote or the direct evolution of the Eukarya from the Archaea. The Eukaryotes First proponents posit that the eukaryotes evolved initially and then, by reductive evolution, produced the Bacteria and Archaea. No mention was made of another previously published hypothesis termed the Nuclear Compartment Commonality (NuCom) hypothesis, which proposed the evolution of the Eukarya and Bacteria from nucleated ancestors (Staley 2013 Astrobiol Outreach 1 , 105 (doi:10.4172/2332-2519.1000105)). Evidence from two studies indicates that the nucleated Planctomycetes-Verrucomicrobia-Chlamydia superphylum members are the most ancient Bacteria known (Brochier & Philippe 2002 Nature 417 , 244 (doi:10.1038/417244a); Jun et al. 2010 Proc. Natl Acad. Sci. USA 107 , 133-138 (doi:10.1073/pnas.0913033107)). This review summarizes the evidence for the NuCom hypothesis and discusses how simple the NuCom hypothesis is in explaining eukaryote evolution relative to the other hypotheses. The philosophical importance of simplicity and its relationship to truth in hypotheses such as NuCom and Domain Cell Theory is presented. Domain Cell Theory is also proposed herein, which contends that each of the three cellular lineages of life, the Archaea, Bacteria and Eukarya domains, evolved independently, in support of the NuCom hypothesis. All other proposed hypotheses violate Domain Cell Theory because they posit the evolution of different cellular descendants from ancestral cellular types. © 2017 The Authors.

Life history of the most complete fossil primate skeleton: exploring growth models for Darwinius

PubMed Central

López-Torres, Sergi; Schillaci, Michael A.; Silcox, Mary T.

2015-01-01

Darwinius is an adapoid primate from the Eocene of Germany, and its only known specimen represents the most complete fossil primate ever found. Its describers hypothesized a close relationship to Anthropoidea, and using a Saimiri model estimated its age at death. This study reconstructs the ancestral permanent dental eruption sequences for basal Euprimates, Haplorhini, Anthropoidea, and stem and crown Strepsirrhini. The results show that the ancestral sequences for the basal euprimate, haplorhine and stem strepsirrhine are identical, and similar to that of Darwinius. However, Darwinius differs from anthropoids by exhibiting early development of the lower third molars relative to the lower third and fourth premolars. The eruption of the lower second premolar marks the point of interruption of the sequence in Darwinius. The anthropoid Saimiri as a model is therefore problematic because it exhibits a delayed eruption of P2. Here, an alternative strepsirrhine model based on Eulemur and Varecia is presented. Our proposed model shows an older age at death than previously suggested (1.05–1.14 years), while the range for adult weight is entirely below the range proposed previously. This alternative model is more consistent with hypotheses supporting a stronger relationship between adapoids and strepsirrhines. PMID:26473056

Determining the Metal/Silicate Partition Coefficient of Germanium: Implications for Core and Mantle Differentiation.

NASA Technical Reports Server (NTRS)

King, C.; Righter, K.; Danielson, L.; Pando, K.; Lee, C.

2010-01-01

Currently there are several hypotheses for the thermal state of the early Earth. Some hypothesize a shallow magma ocean, or deep magma ocean, or heterogeneous accretion which requires no magma ocean at all. Previous models are unable to account for Ge depletion in Earth's mantle relative to CI chondrites. In this study, the element Ge is used to observe the way siderophile elements partition into the metallic core. The purpose of this research is to provide new data for Ge and to further test these models for Earth's early stages. The partition coefficients (D(sub Ge) = c(sub metal)/c(sub silicate), where D = partition coefficient of Ge and c = concentration of Ge in the metal and silicate, respectively) of siderophile elements were studied by performing series of high pressure, high temperature experiments. They are also dependent on oxygen fugacity, and metal and silicate composition. Ge is a moderately siderophile element found in both the mantle and core, and has yet to be studied systematically at high temperatures. Moreover, previous work has been limited by the low solubility of Ge in silicate melts (less than 100 ppm and close to detection limits for electron microprobe analysis). Reported here are results from 14 experiments studying the partitioning of Ge between silicate and metallic liquids. The Ge concentrations were then analyzed using Laser Ablation Inductively Coupled Mass Spectrometry (LA-ICP-MS) which is sensitive enough to detect ppm levels of Ge in the silicate melt.

Induction Based on Circumscription

NASA Astrophysics Data System (ADS)

Saito, Haruka; Inoue, Katsumi

We investigate induction from the viewpoint of nonmonotonic reasoning. Induction we consider in this paper is descriptive induction. Hypotheses from descriptive induction have the weak property that they only describe rules with respect to the observations and do not realize an inductive leap. In this paper, we define a new form of descriptive induction with circumscription and the idea of explanation and show two procedures for computing it. The new descriptive induction is called circumscriptive induction. By deciding the roles of predicates in circumscription, we can intentionally minimize models of a given inductive problem. By adopting the idea of explanation, we can distinguish between background knowledge and observations. Additionally, we consider the relationship between the way of choosing the roles of predicates in computing circumscription and the property of hypotheses obtained by circumscriptive induction. It is shown that hypotheses from circumscriptive induction reflect a difference between background knowledge and observations and do not realize an inductive leap. We also investigate revision of hypotheses which is as important as generation of hypotheses. In a process of hypothesis revision, a difference between previous induction and circumscriptive induction is clearly characterised.

The public's trust in scientific claims regarding offshore oil drilling.

PubMed

Carlisle, Juliet E; Feezell, Jessica T; Michaud, Kristy E H; Smith, Eric R A N; Smith, Leeanna

2010-09-01

Our study examines how individuals decide which scientific claims and experts to believe when faced with competing claims regarding a policy issue. Using an experiment in a public opinion survey, we test the source content and credibility hypotheses to assess how much confidence people have in reports about scientific studies of the safety of offshore oil drilling along the California coast. The results show that message content has a substantial impact. People tend to accept reports of scientific studies that support their values and prior beliefs, but not studies that contradict them. Previous studies have shown that core values influence message acceptance. We find that core values and prior beliefs have independent effects on message acceptance. We also find that the sources of the claims make little difference. Finally, the public leans toward believing reports that oil drilling is riskier than previously believed.

Exposure and non-fear emotions: A randomized controlled study of exposure-based and rescripting-based imagery in PTSD treatment.

PubMed

Langkaas, Tomas Formo; Hoffart, Asle; Øktedalen, Tuva; Ulvenes, Pål G; Hembree, Elizabeth A; Smucker, Mervin

2017-10-01

Interventions involving rescripting-based imagery have been proposed as a better approach than exposure-based imagery when posttraumatic stress disorder (PTSD) is associated with emotions other than fear. Prior research led to the study's hypotheses that (a) higher pretreatment non-fear emotions would predict relatively better response to rescripting as compared to exposure, (b) rescripting would be associated with greater reduction in non-fear emotions, and (c) pretreatment non-fear emotions would predict poor response to exposure. A clinically representative sample of 65 patients presenting a wide range of traumas was recruited from patients seeking and being offered PTSD treatment in an inpatient setting. Subjects were randomly assigned to 10 weeks of treatment involving either rescripting-based imagery (Imagery Rescripting; IR) or exposure-based imagery (Prolonged Exposure; PE). Patients were assessed on outcome and emotion measures at pretreatment, posttreatment and 12 months follow-up. Comparison to control benchmarks indicated that both treatments were effective, but no outcome differences between them appeared. None of the initial hypotheses were supported. The results from this study challenge previous observations and hypotheses about exposure mainly being effective for fear-based PTSD and strengthen the notion that exposure-based treatment is a generally effective treatment for all types of PTSD. Copyright © 2017 Elsevier Ltd. All rights reserved.

Ordinal Position, Sex of Sibling, Sex, and Personal Preferences in a Group of Eighteen Year Olds

ERIC Educational Resources Information Center

Oberlander, Mark I.; And Others

1970-01-01

Investigates three hypotheses derived from previous research, that different ordinal position groups manifest differential personal preference patterns, as measured by the Kuder Preference Record. (Author)

Ancestral state reconstructions require biological evidence to test evolutionary hypotheses: A case study examining the evolution of reproductive mode in squamate reptiles.

PubMed

Griffith, Oliver W; Blackburn, Daniel G; Brandley, Matthew C; Van Dyke, James U; Whittington, Camilla M; Thompson, Michael B

2015-09-01

To understand evolutionary transformations it is necessary to identify the character states of extinct ancestors. Ancestral character state reconstruction is inherently difficult because it requires an accurate phylogeny, character state data, and a statistical model of transition rates and is fundamentally constrained by missing data such as extinct taxa. We argue that model based ancestral character state reconstruction should be used to generate hypotheses but should not be considered an analytical endpoint. Using the evolution of viviparity and reversals to oviparity in squamates as a case study, we show how anatomical, physiological, and ecological data can be used to evaluate hypotheses about evolutionary transitions. The evolution of squamate viviparity requires changes to the timing of reproductive events and the successive loss of features responsible for building an eggshell. A reversal to oviparity requires that those lost traits re-evolve. We argue that the re-evolution of oviparity is inherently more difficult than the reverse. We outline how the inviability of intermediate phenotypes might present physiological barriers to reversals from viviparity to oviparity. Finally, we show that ecological data supports an oviparous ancestral state for squamates and multiple transitions to viviparity. In summary, we conclude that the first squamates were oviparous, that frequent transitions to viviparity have occurred, and that reversals to oviparity in viviparous lineages either have not occurred or are exceedingly rare. As this evidence supports conclusions that differ from previous ancestral state reconstructions, our paper highlights the importance of incorporating biological evidence to evaluate model-generated hypotheses. © 2015 Wiley Periodicals, Inc.

Personality at midlife: stability, intrinsic maturation, and response to life events.

PubMed

Costa, P T; Herbst, J H; McCrae, R R; Siegler, I C

2000-12-01

Although developmental theories and popular accounts suggest that midlife is a time of turmoil and change, longitudinal studies of personality traits have generally found stability of rank order and little or no change in mean levels. Using data from 2,274 men and women in their 40s retested after 6 to 9 years, the present study examined two hypotheses: (a) that retest correlations should be no higher than about .60 and (b) that there should be small decreases in Neuroticism, Extraversion, and Openness, and small increases in Agreeableness and Conscientiousness. The study also explored the effects of recalled life events on subsequent personality scores. Results did not support the first hypothesis; uncorrected retest correlations uniformly exceeded .60. This was true for all personality traits, including facets of Agreeableness and Conscientiousness not previously included in longitudinal studies. The hypothesized decreases in Neuroticism, Extraversion, and Openness were found, but Conscientiousness showed a small decrease instead of the predicted increase. Life events in general showed very little influence on the levels of personality traits, although some effects were seen for changes in job and marital status that warrant further research.

Relation Between Selected Water-Quality Variables, Climatic Factors, and Lake Levels in Upper Klamath and Agency Lakes, Oregon, 1990-2006

USGS Publications Warehouse

Morace, Jennifer L.

2007-01-01

Growth and decomposition of dense blooms of Aphanizomenon flos-aquae in Upper Klamath Lake frequently cause extreme water-quality conditions that have led to critical fishery concerns for the region, including the listing of two species of endemic suckers as endangered. The Bureau of Reclamation has asked the U.S. Geological Survey (USGS) to examine water-quality data collected by the Klamath Tribes for relations with lake level. This analysis evaluates a 17-year dataset (1990-2006) and updates a previous USGS analysis of a 5-year dataset (1990-94). Both univariate hypothesis testing and multivariable analyses evaluated using an information-theoretic approach revealed the same results-no one overarching factor emerged from the data. No single factor could be relegated from consideration either. The lack of statistically significant, strong correlations between water-quality conditions, lake level, and climatic factors does not necessarily show that these factors do not influence water-quality conditions; it is more likely that these conditions work in conjunction with each other to affect water quality. A few different conclusions could be drawn from the larger dataset than from the smaller dataset examined in 1996, but for the most part, the outcome was the same. Using an observational dataset that may not capture all variation in water-quality conditions (samples were collected on a two-week interval) and that has a limited range of conditions for evaluation (confined to the operation of lake) may have confounded the exploration of explanatory factors. In the end, all years experienced some variation in poor water-quality conditions, either in timing of occurrence of the poor conditions or in their duration. The dataset of 17 years simply provided 17 different patterns of lake level, cumulative degree-days, timing of the bloom onset, and poor water-quality conditions, with no overriding causal factor emerging from the variations. Water-quality conditions were evaluated for their potential to be harmful to the endangered sucker species on the basis of high-stress thresholds-water temperature values greater than 28 degrees Celsius, dissolved-oxygen concentrations less than 4 milligrams per liter, and pH values greater than 9.7. Few water temperatures were greater than 28 degrees Celsius, and dissolved-oxygen concentrations less than 4 milligrams per liter generally were recorded in mid to late summer. In contrast, high pH values were more frequent, occurring earlier in the season and parallel with growth in the algal bloom. The 10 hypotheses relating water-quality variables, lake level, and climatic factors from the earlier USGS study were tested in this analysis for the larger 1990-2006 dataset. These hypotheses proposed relations between lake level and chlorophyll-a, pH, dissolved oxygen, total phosphorus, and water temperature. As in the previous study, no evidence was found in the larger dataset for any of these relations based on a seasonal (May-October) distribution. When analyzing only the June data, the previous 5-year study did find evidence for three hypotheses relating lake level to the onset of the bloom, chlorophyll-a concentrations, and the frequency of high pH values in June. These hypotheses were not supported by the 1990-2006 dataset, but the two hypotheses related to cumulative degree-days from the previous study were: chlorophyll-a concentrations were lower and onset of the algal bloom was delayed when spring air temperatures were cooler. Other relations between water-quality variables and cumulative degree-days were not significant. In an attempt to identify interrelations among variables not detected by univariate analysis, multiple regressions were performed between lakewide measures of low dissolved-oxygen concentrations or high pH values in July and August and six physical and biological variables (peak chlorophyll-a concentrations, degree-days, water temperature, median October-May discharg

Effect of Space Flight on Adrenal Medullary Function

NASA Technical Reports Server (NTRS)

Lelkes, Peter I.

1999-01-01

We hypothesize that microgravity conditions during space flight alter the expression and specific activities of the adrenal medullary CA synthesizing enzymes (CASE). Previously, we examined adrenals from six rats flown for six days aboard STS 54 and reported that microgravity induced a decrease in the expression and specific activity of rat adrenal medullary tyrosine hydroxylase, the rate limiting enzyme of CA synthesis, without affecting the expression of other CASE. In the past, we analyzed some of the > 300 adrenals from two previous Space Shuttle missions (PARE 03 and SLS 2). The preliminary results (a) attest to the good state of tissue preservation, thus proving the feasibility of subsequent large-scale evaluation, and (b) confirm and extend our previous findings. With this grant we will be able to expeditiously analyze all our specimens and to complete our studies in a timely fashion.

Extending Previous cG×I Findings on 5-HTTLPR's Moderation of Intervention Effects on Adolescent Substance Misuse Initiation.

PubMed

Schlomer, Gabriel L; Cleveland, H Harrington; Feinberg, Mark E; Wolf, Pedro S A; Greenberg, Mark T; Spoth, Richard L; Redmond, Cleve; Tricou, Eric P; Vandenbergh, David J

2017-11-01

This study addresses replication in candidate gene × environment interaction (cG×E) research by investigating if the key findings from Brody, Beach, Philibert, Chen, and Murry (2009) can be detected using data (N = 1,809) from the PROSPER substance use preventive intervention delivery system. Parallel to Brody et al., this study tested the hypotheses that substance misuse initiation would increase faster from age 11 to age 14 and be higher at age 14 among: (a) 5-HTTLPR short carrier adolescents versus long homozygotes, (b) control versus intervention adolescents, and (c) 5-HTTLPR short carriers in the control condition versus all other participants. The hypotheses were generally supported and results were consistent with Brody et al.'s cG×I finding. Results are discussed in light of replication issues in cG×E research and implications for intervention. © 2016 The Authors. Child Development © 2016 Society for Research in Child Development, Inc.

Biological Insights From 108 Schizophrenia-Associated Genetic Loci

PubMed Central

Ripke, Stephan; Neale, Benjamin M; Corvin, Aiden; Walters, James TR; Farh, Kai-How; Holmans, Peter A; Lee, Phil; Bulik-Sullivan, Brendan; Collier, David A; Huang, Hailiang; Pers, Tune H; Agartz, Ingrid; Agerbo, Esben; Albus, Margot; Alexander, Madeline; Amin, Farooq; Bacanu, Silviu A; Begemann, Martin; Belliveau, Richard A; Bene, Judit; Bergen, Sarah E; Bevilacqua, Elizabeth; Bigdeli, Tim B; Black, Donald W; Bruggeman, Richard; Buccola, Nancy G; Buckner, Randy L; Byerley, William; Cahn, Wiepke; Cai, Guiqing; Campion, Dominique; Cantor, Rita M; Carr, Vaughan J; Carrera, Noa; Catts, Stanley V; Chambert, Kimberley D; Chan, Raymond CK; Chan, Ronald YL; Chen, Eric YH; Cheng, Wei; Cheung, Eric FC; Chong, Siow Ann; Cloninger, C Robert; Cohen, David; Cohen, Nadine; Cormican, Paul; Craddock, Nick; Crowley, James J; Curtis, David; Davidson, Michael; Davis, Kenneth L; Degenhardt, Franziska; Del Favero, Jurgen; Demontis, Ditte; Dikeos, Dimitris; Dinan, Timothy; Djurovic, Srdjan; Donohoe, Gary; Drapeau, Elodie; Duan, Jubao; Dudbridge, Frank; Durmishi, Naser; Eichhammer, Peter; Eriksson, Johan; Escott-Price, Valentina; Essioux, Laurent; Fanous, Ayman H; Farrell, Martilias S; Frank, Josef; Franke, Lude; Freedman, Robert; Freimer, Nelson B; Friedl, Marion; Friedman, Joseph I; Fromer, Menachem; Genovese, Giulio; Georgieva, Lyudmila; Giegling, Ina; Giusti-Rodríguez, Paola; Godard, Stephanie; Goldstein, Jacqueline I; Golimbet, Vera; Gopal, Srihari; Gratten, Jacob; de Haan, Lieuwe; Hammer, Christian; Hamshere, Marian L; Hansen, Mark; Hansen, Thomas; Haroutunian, Vahram; Hartmann, Annette M; Henskens, Frans A; Herms, Stefan; Hirschhorn, Joel N; Hoffmann, Per; Hofman, Andrea; Hollegaard, Mads V; Hougaard, David M; Ikeda, Masashi; Joa, Inge; Julià, Antonio; Kahn, René S; Kalaydjieva, Luba; Karachanak-Yankova, Sena; Karjalainen, Juha; Kavanagh, David; Keller, Matthew C; Kennedy, James L; Khrunin, Andrey; Kim, Yunjung; Klovins, Janis; Knowles, James A; Konte, Bettina; Kucinskas, Vaidutis; Kucinskiene, Zita Ausrele; Kuzelova-Ptackova, Hana; Kähler, Anna K; Laurent, Claudine; Lee, Jimmy; Lee, S Hong; Legge, Sophie E; Lerer, Bernard; Li, Miaoxin; Li, Tao; Liang, Kung-Yee; Lieberman, Jeffrey; Limborska, Svetlana; Loughland, Carmel M; Lubinski, Jan; Lönnqvist, Jouko; Macek, Milan; Magnusson, Patrik KE; Maher, Brion S; Maier, Wolfgang; Mallet, Jacques; Marsal, Sara; Mattheisen, Manuel; Mattingsdal, Morten; McCarley, Robert W; McDonald, Colm; McIntosh, Andrew M; Meier, Sandra; Meijer, Carin J; Melegh, Bela; Melle, Ingrid; Mesholam-Gately, Raquelle I; Metspalu, Andres; Michie, Patricia T; Milani, Lili; Milanova, Vihra; Mokrab, Younes; Morris, Derek W; Mors, Ole; Murphy, Kieran C; Murray, Robin M; Myin-Germeys, Inez; Müller-Myhsok, Bertram; Nelis, Mari; Nenadic, Igor; Nertney, Deborah A; Nestadt, Gerald; Nicodemus, Kristin K; Nikitina-Zake, Liene; Nisenbaum, Laura; Nordin, Annelie; O’Callaghan, Eadbhard; O’Dushlaine, Colm; O’Neill, F Anthony; Oh, Sang-Yun; Olincy, Ann; Olsen, Line; Van Os, Jim; Pantelis, Christos; Papadimitriou, George N; Papiol, Sergi; Parkhomenko, Elena; Pato, Michele T; Paunio, Tiina; Pejovic-Milovancevic, Milica; Perkins, Diana O; Pietiläinen, Olli; Pimm, Jonathan; Pocklington, Andrew J; Powell, John; Price, Alkes; Pulver, Ann E; Purcell, Shaun M; Quested, Digby; Rasmussen, Henrik B; Reichenberg, Abraham; Reimers, Mark A; Richards, Alexander L; Roffman, Joshua L; Roussos, Panos; Ruderfer, Douglas M; Salomaa, Veikko; Sanders, Alan R; Schall, Ulrich; Schubert, Christian R; Schulze, Thomas G; Schwab, Sibylle G; Scolnick, Edward M; Scott, Rodney J; Seidman, Larry J; Shi, Jianxin; Sigurdsson, Engilbert; Silagadze, Teimuraz; Silverman, Jeremy M; Sim, Kang; Slominsky, Petr; Smoller, Jordan W; So, Hon-Cheong; Spencer, Chris C A; Stahl, Eli A; Stefansson, Hreinn; Steinberg, Stacy; Stogmann, Elisabeth; Straub, Richard E; Strengman, Eric; Strohmaier, Jana; Stroup, T Scott; Subramaniam, Mythily; Suvisaari, Jaana; Svrakic, Dragan M; Szatkiewicz, Jin P; Söderman, Erik; Thirumalai, Srinivas; Toncheva, Draga; Tosato, Sarah; Veijola, Juha; Waddington, John; Walsh, Dermot; Wang, Dai; Wang, Qiang; Webb, Bradley T; Weiser, Mark; Wildenauer, Dieter B; Williams, Nigel M; Williams, Stephanie; Witt, Stephanie H; Wolen, Aaron R; Wong, Emily HM; Wormley, Brandon K; Xi, Hualin Simon; Zai, Clement C; Zheng, Xuebin; Zimprich, Fritz; Wray, Naomi R; Stefansson, Kari; Visscher, Peter M; Adolfsson, Rolf; Andreassen, Ole A; Blackwood, Douglas HR; Bramon, Elvira; Buxbaum, Joseph D; Børglum, Anders D; Cichon, Sven; Darvasi, Ariel; Domenici, Enrico; Ehrenreich, Hannelore; Esko, Tõnu; Gejman, Pablo V; Gill, Michael; Gurling, Hugh; Hultman, Christina M; Iwata, Nakao; Jablensky, Assen V; Jönsson, Erik G; Kendler, Kenneth S; Kirov, George; Knight, Jo; Lencz, Todd; Levinson, Douglas F; Li, Qingqin S; Liu, Jianjun; Malhotra, Anil K; McCarroll, Steven A; McQuillin, Andrew; Moran, Jennifer L; Mortensen, Preben B; Mowry, Bryan J; Nöthen, Markus M; Ophoff, Roel A; Owen, Michael J; Palotie, Aarno; Pato, Carlos N; Petryshen, Tracey L; Posthuma, Danielle; Rietschel, Marcella; Riley, Brien P; Rujescu, Dan; Sham, Pak C; Sklar, Pamela; St Clair, David; Weinberger, Daniel R; Wendland, Jens R; Werge, Thomas; Daly, Mark J; Sullivan, Patrick F; O’Donovan, Michael C

2014-01-01

Summary Schizophrenia is a highly heritable disorder. Genetic risk is conferred by a large number of alleles, including common alleles of small effect that might be detected by genome-wide association studies. Here, we report a multi-stage schizophrenia genome-wide association study of up to 36,989 cases and 113,075 controls. We identify 128 independent associations spanning 108 conservatively defined loci that meet genome-wide significance, 83 of which have not been previously reported. Associations were enriched among genes expressed in brain providing biological plausibility for the findings. Many findings have the potential to provide entirely novel insights into aetiology, but associations at DRD2 and multiple genes involved in glutamatergic neurotransmission highlight molecules of known and potential therapeutic relevance to schizophrenia, and are consistent with leading pathophysiological hypotheses. Independent of genes expressed in brain, associations were enriched among genes expressed in tissues that play important roles in immunity, providing support for the hypothesized link between the immune system and schizophrenia. PMID:25056061

Knowledge discovery from structured mammography reports using inductive logic programming.

PubMed

Burnside, Elizabeth S; Davis, Jesse; Costa, Victor Santos; Dutra, Inês de Castro; Kahn, Charles E; Fine, Jason; Page, David

2005-01-01

The development of large mammography databases provides an opportunity for knowledge discovery and data mining techniques to recognize patterns not previously appreciated. Using a database from a breast imaging practice containing patient risk factors, imaging findings, and biopsy results, we tested whether inductive logic programming (ILP) could discover interesting hypotheses that could subsequently be tested and validated. The ILP algorithm discovered two hypotheses from the data that were 1) judged as interesting by a subspecialty trained mammographer and 2) validated by analysis of the data itself.

Spillover Effects of Loss of Control on Risky Decision-Making

PubMed Central

Beisswingert, Birgit M.; Zhang, Keshun; Goetz, Thomas; Fischbacher, Urs

2016-01-01

Decision making in risky situations is frequently required in our everyday lives and has been shown to be influenced by various factors, some of which are independent of the risk context. Based on previous findings and theories about the central role of perceptions of control and their impact on subsequent settings, spillover effects of subjective loss of control on risky decision-making are assumed. After developing an innovative experimental paradigm for inducing loss of control, its hypothesized effects on risky decision-making are investigated. Partially supporting the hypotheses, results demonstrated no increased levels of risk perceptions but decreased risk-taking behavior following experiences of loss of control. Thus, this study makes a methodological contribution by proposing a newly developed experimental paradigm facilitating further research on the effects of subjective loss of control, and additionally provides partial evidence for the spillover effects of loss of control experiences on risky decision-making. PMID:26930066

Relating Worry and Executive Functioning During Childhood: The Moderating Role of Age.

PubMed

Geronimi, Elena M C; Patterson, Heather L; Woodruff-Borden, Janet

2016-06-01

The associations between worry and executive functioning across development have not been previously explored. Examining the interrelationships between these variables in childhood may further elucidate the cognitive nature of worry as well as its developmental course. Hypotheses predicted that difficulties with executive functioning would correlate with child worry; based on extant literature, age-related hypotheses were proposed for particular aspects of executive functioning. Children (N = 130) participated in the present study. Difficulties with executive functioning and child worry were assessed. Results demonstrated that each executive functioning subscale correlated with worry. The relations between worry and several facets of executive functioning were no longer significant at older ages, while the relations between worry and the facets of inhibition, shifting, and emotional control did not demonstrate age-related interaction effects. Overall, the findings suggest that worry is associated with executive functioning at young ages and that this association takes distinct forms during different childhood stages.

Biomedical hypothesis generation by text mining and gene prioritization.

PubMed

Petric, Ingrid; Ligeti, Balazs; Gyorffy, Balazs; Pongor, Sandor

2014-01-01

Text mining methods can facilitate the generation of biomedical hypotheses by suggesting novel associations between diseases and genes. Previously, we developed a rare-term model called RaJoLink (Petric et al, J. Biomed. Inform. 42(2): 219-227, 2009) in which hypotheses are formulated on the basis of terms rarely associated with a target domain. Since many current medical hypotheses are formulated in terms of molecular entities and molecular mechanisms, here we extend the methodology to proteins and genes, using a standardized vocabulary as well as a gene/protein network model. The proposed enhanced RaJoLink rare-term model combines text mining and gene prioritization approaches. Its utility is illustrated by finding known as well as potential gene-disease associations in ovarian cancer using MEDLINE abstracts and the STRING database.

A phylogenetic analysis of Diurideae (Orchidaceae) based on plastid DNA sequence data.

PubMed

Kores, P J; Molvray, M; Weston, P H; Hopper, S D; Brown, A P; Cameron, K M; Chase, M W

2001-10-01

DNA sequence data from plastid matK and trnL-F regions were used in phylogenetic analyses of Diurideae, which indicate that Diurideae are not monophyletic as currently delimited. However, if Chloraeinae and Pterostylidinae are excluded from Diurideae, the remaining subtribes form a well-supported, monophyletic group that is sister to a "spiranthid" clade. Chloraea, Gavilea, and Megastylis pro parte (Chloraeinae) are all placed among the spiranthid orchids and form a grade with Pterostylis leading to a monophyletic Cranichideae. Codonorchis, previously included among Chloraeinae, is sister to Orchideae. Within the more narrowly delimited Diurideae two major lineages are apparent. One includes Diuridinae, Cryptostylidinae, Thelymitrinae, and an expanded Drakaeinae; the other includes Caladeniinae s.s., Prasophyllinae, and Acianthinae. The achlorophyllous subtribe Rhizanthellinae is a member of Diurideae, but its placement is otherwise uncertain. The sequence-based trees indicate that some morphological characters used in previous classifications, such as subterranean storage organs, anther position, growth habit, fungal symbionts, and pollination syndromes have more complex evolutionary histories than previously hypothesized. Treatments based upon these characters have produced conflicting classifications, and molecular data offer a tool for reevaluating these phylogenetic hypotheses.

Why Does the “Sinner” Act Prosocially? The Mediating Role of Guilt and the Moderating Role of Moral Identity in Motivating Moral Cleansing

PubMed Central

Ding, Wan; Xie, Ruibo; Sun, Binghai; Li, Weijian; Wang, Duo; Zhen, Rui

2016-01-01

Numerous studies have found that people tend to commit prosocial acts subsequent to previous immoral acts, as a response to the latter. This phenomenon is called moral cleansing or moral compensation. However, the specific mechanism how previous immoral acts motivate moral compensatory behaviors is still not fully understood. This study aimed to examine the roles of guilt and moral identity in the relation between previous immoral acts and subsequent prosocial behaviors to clarify the mechanism. Based on the extant research, the current study proposed a moderated mediation model to illustrate the process of moral cleansing. Specifically, a previous immoral act motivates guilt, which further leads to subsequent prosocial behaviors, while moral identity facilitates this process. The participants were primed by a recalling task (immoral act vs. a neutral event). The results support the hypothesized model and provide a framework that explains moral cleansing by integrating the roles of guilt and moral identity. These findings highlight the dynamic nature of people’s morality with regard to how people adapt moral behaviors to protect their moral self-image. PMID:27660617

Attention deficit hyperactivity disorder may be a highly inflammation and immune-associated disease (Review).

PubMed

Zhou, Rong-Yi; Wang, Jiao-Jiao; Sun, Ji-Chao; You, Yue; Ying, Jing-Nang; Han, Xin-Min

2017-10-01

Attention deficit hyperactivity disorder (ADHD) is a common behavioral disorder. Previous research has indicated that genetic factors, family education, environment and dietary habits are associated with ADHD. It has been determined that in China many children with ADHD also have allergic rhinitis or asthma. These children are more susceptible to the common cold or upper respiratory infections compared with normal healthy children. Additionally, the common cold or an upper respiratory infection may lead to disease recurrence or worsen the symptoms in these children. Previous studies have determined that ADHD may have a close association with allergic disease. Based on the clinically observed phenomenon and previous studies, it was hypothesized that ADHD is a high inflammation and immune‑associated disease. Therefore, the authors designed clinical and animal experiments to test this hypothesis in the future. Immune system disorders may be a novel part of the etiology of ADHD. The current report may have implications for future clinical practice.

Neuropsychological function and past exposure to metallic mercury in female dental workers

PubMed Central

Sletvold, Helge; Svendsen, Kristin; Aas, Oddfrid; Syversen, Tore; Hilt, Bjørn

2012-01-01

The aim of this study was to see if dental personnel with previous exposure to metallic mercury have later developed disturbances in cognitive function. Ninety-one female participants who had been selected from a previous health survey of dental personnel were investigated neuropsychologically within the following domains: motor function, short-term memory, working memory, executive function, mental flexibility, and visual and verbal long-term memory. The scores were mainly within normal ranges. Relationships between an exposure score, the duration of employment before 1990, and previously measured mercury in urine as independent variables and the neuropsychological findings as dependent variables, were analyzed by multiple linear regression controlling for age, general ability, length of education, alcohol consumption, and previous head injuries. The only relationship that was statistically significant in the hypothesized direction was between the previously measured urine mercury values and visual long-term memory, where the urine values explained 30% of the variability. As the study had a low statistical power and also some other methodological limitations, the results have to be interpreted with caution. Even so, we think it is right to conclude that neuropsychological findings indicative of subsequent cognitive injuries are difficult to find in groups of otherwise healthy dental personnel with previous occupational exposure to mercury. PMID:22092046

Deer Mates: A Quantitative Study of Heterospecific Sexual Behaviors Performed by Japanese Macaques Toward Sika Deer.

PubMed

Gunst, Noëlle; Vasey, Paul L; Leca, Jean-Baptiste

2018-05-01

This is the first quantitative study of heterospecific sexual behavior between a non-human primate and a non-primate species. We observed multiple occurrences of free-ranging adolescent female Japanese macaques (Macaca fuscata) performing mounts and sexual solicitations toward sika deer (Cervus nippon) at Minoo, central Japan. Our comparative description of monkey-deer versus monkey-monkey interactions supported the "heterospecific sexual behavior" hypothesis: the mounts and demonstrative solicitations performed by adolescent female Japanese macaques toward sika deer were sexual in nature. In line with our previous research on the development of homospecific sexual behavior in immature female Japanese macaques, this study will allow us to test other hypotheses in the future, such as the "practice for homospecific sex," the "safe sex," the "homospecific sex deprivation," the "developmental by-product," and the "cultural heterospecific sex" hypotheses. Further research will be necessary to ascertain whether this group-specific sexual behavior was a short-lived fad or an incipient cultural phenomenon and may also contribute to better understanding the proximate and ultimate causes of reproductive interference.

Reducing self-objectification: are dissonance-based methods a possible approach?

PubMed Central

2013-01-01

Background Previous research has documented that self-objectification is associated with numerous negative outcomes including body shame, eating disorder (ED) pathology, and negative affect. This exploratory open study investigated whether or not an evidence-based body image improvement program that targets thin-ideal internalization in university women also reduces self-objectification. A second aim of the study was to determine if previous findings showing that body shame mediated the relationship between self-objectification and eating disorder pathology at a single time point (consistent with self-objectification theory) but did not mediate longitudinally (inconsistent with self-objectification theory) would be replicated in a new sample under novel conditions. Methods Ninety-six university women completed a peer-led dissonance-based intervention, along with assessment measures at pre-, post-intervention, 8-week and 8-month follow-up. To address the open trial nature of this study, a planned manipulation check was included to make sure that peer-led dissonance decreased thin-ideal internalization, body dissatisfaction, eating disorder pathology, and negative affect with effect sizes being similar to past randomized controlled trials. We hypothesized that all three subscales of the Objectified Body Consciousness Scale (i.e., self-surveillance, body shame, and appearance control beliefs) would be reduced. In addition, we hypothesized that body shame would mediate the relationship between self-objectification (i.e., self-surveillance) and eating disorder pathology at a both at a single time point and longitudinally. Results The planned manipulation check supported the interpretation that peer-led dissonance in this study largely yielded comparable changes to past controlled trials. In terms of changes in dependent variables, results supported all hypotheses with the exception of body shame, which remained unchanged. With regards to the mediation analyses, our first (cross-sectional) hypothesis but not our second (longitudinal) was supported. Conclusions Findings provide preliminary support for the use of dissonance interventions in reducing self-surveillance and body control beliefs. Results for body shame and the mediation analyses suggest that greater scrutiny of the body shame construct is warranted. PMID:24999392

Ecological optimality in water-limited natural soil-vegetation systems. II - Tests and applications

NASA Technical Reports Server (NTRS)

Eagleson, P. S.; Tellers, T. E.

1982-01-01

The long-term optimal climatic climax soil-vegetation system is defined for several climates according to previous hypotheses in terms of two free parameters, effective porosity and plant water use coefficient. The free parameters are chosen by matching the predicted and observed average annual water yield. The resulting climax soil and vegetation properties are tested by comparison with independent observations of canopy density and average annual surface runoff. The climax properties are shown also to satisfy a previous hypothesis for short-term optimization of canopy density and water use coefficient. Using these hypotheses, a relationship between average evapotranspiration and optimum vegetation canopy density is derived and is compared with additional field observations. An algorithm is suggested by which the climax soil and vegetation properties can be calculated given only the climate parameters and the soil effective porosity. Sensitivity of the climax properties to the effective porosity is explored.

The origin of downbeat nystagmus: an asymmetry in the distribution of on-directions of vertical gaze-velocity Purkinje cells.

PubMed

Marti, Sarah; Straumann, Dominik; Glasauer, Stefan

2005-04-01

Various hypotheses on the origin of cerebellar downbeat nystagmus (DBN) have been presented; the exact pathomechanism, however, is still not known. Based on previous anatomical and electrophysiological studies, we propose that an asymmetry in the distribution of on-directions of vertical gaze-velocity Purkinje cells leads to spontaneous upward ocular drift in cerebellar disease, and therefore, to DBN. Our hypothesis is supported by a computational model for vertical eye movements.

The Role of Prediction In Perception: Evidence From Interrupted Visual Search

PubMed Central

Mereu, Stefania; Zacks, Jeffrey M.; Kurby, Christopher A.; Lleras, Alejandro

2014-01-01

Recent studies of rapid resumption—an observer’s ability to quickly resume a visual search after an interruption—suggest that predictions underlie visual perception. Previous studies showed that when the search display changes unpredictably after the interruption, rapid resumption disappears. This conclusion is at odds with our everyday experience, where the visual system seems to be quite efficient despite continuous changes of the visual scene; however, in the real world, changes can typically be anticipated based on previous knowledge. The present study aimed to evaluate whether changes to the visual display can be incorporated into the perceptual hypotheses, if observers are allowed to anticipate such changes. Results strongly suggest that an interrupted visual search can be rapidly resumed even when information in the display has changed after the interruption, so long as participants not only can anticipate them, but also are aware that such changes might occur. PMID:24820440

Experimental Investigation into the Radar Anomalies on the Surface of Venus

NASA Technical Reports Server (NTRS)

Kohler, E.; Gavin, P.; Chevrier, V.; Johnson, Natasha M.

2012-01-01

Radar mapping of thc surface of Venus shows areas of high reflectivity (low emissivity) in the Venusian highlands at altitudes between 2.5-4.75 kilometers. The origin of the radar anomalies found in the Venusian highlands remains unclear. Most explanations of the potential causes for these radar anomalies come from theoretical work. Previous studies suggest increased surface roughness or materials with higher dielectric constants as well as surface atmospheric interactions. Several possible candidates of high-dielectric materials are tellurium) ferroelectric materials, and lead or bismuth sulfides. While previous studies have been influential in determining possible sources for the Venus anomalies, only a very few hypotheses have been verified via experimentation. This work intends to experimentally constrain the source of the radar anomalies on Venus. This study proposes to investigate four possible materials that could potentially cause the high reflectivities on the surface of Venus and tests their behavior under simulated Venusian conditions.

Analysis of coiled stator ultrasound motor: Fundamental study on analysis of wave propagation on acoustic waveguide for coiled stator

NASA Astrophysics Data System (ADS)

Ozeki, Seiya; Kurita, Keisuke; Uehara, Choyu; Nakane, Noriaki; Sato, Toshio; Takeuchi, Shinichi

2018-07-01

In our research group, we previously developed a coiled stator ultrasound motor (CS-USM) for medical applications such as intravascular ultrasound (IVUS) devices. However, wave propagation on acoustic waveguides has not been investigated sufficiently in previous studies. In this study, we analyze the propagation velocity of elastic waves from the simulated the vibration displacement mode profile along a straight line acoustic waveguide via three-dimensional finite element method (FEM). Concerning results, elastic waves with vibration displacement along the thickness direction show dispersion characteristics corresponding to the a0 and a1 mode plate waves (Lamb waves) in the acoustic waveguide. Our theoretical hypotheses of the propagation velocities were closely borne out by experimental results. We further find that the dispersion characteristic is affected by the width of the acoustic waveguide. We believe that our findings can contribute to improved CS-USM designs for practical application.

Feared consequences of panic attacks in panic disorder: a qualitative and quantitative analysis.

PubMed

Raffa, Susan D; White, Kamila S; Barlow, David H

2004-01-01

Cognitions are hypothesized to play a central role in panic disorder (PD). Previous studies have used questionnaires to assess cognitive content, focusing on prototypical cognitions associated with PD; however, few studies have qualitatively examined cognitions associated with the feared consequences of panic attacks. The purpose of this study was to conduct a qualitative and quantitative analysis of feared consequences of panic attacks. The initial, qualitative analysis resulted in the development of 32 categories of feared consequences. The categories were derived from participant responses to a standardized, semi-structured question (n = 207). Five expert-derived categories were then utilized to quantitatively examine the relationship between cognitions and indicators of PD severity. Cognitions did not predict PD severity; however, correlational analyses indicated some predictive validity to the expert-derived categories. The qualitative analysis identified additional areas of patient-reported concern not included in previous research that may be important in the assessment and treatment of PD.

Merging Hydrologic, Geochemical, and Geophysical Approaches to Understand the Regolith Architecture of a Deeply Weathered Piedmont Critical Zone

NASA Astrophysics Data System (ADS)

Cosans, C.; Moore, J.; Harman, C. J.

2017-12-01

Located in the deeply weathered Piedmont in Maryland, Pond Branch has a rich legacy of hydrological and geochemical research dating back to the first geochemical mass balance study published in 1970. More recently, geophysical investigations including seismic and electrical resistivity tomography have characterized the subsurface at Pond Branch and contributed to new hypotheses about critical zone evolution. Heterogeneity in electrical resistivity in the shallow subsurface may suggest disparate flow paths for recharge, with some regions with low hydraulic conductivity generating perched flow, while other hillslope sections recharge to the much deeper regolith boundary. These shallow and deep flow paths are hypothesized to be somewhat hydrologically and chemically connected, with the spatially and temporally discontinuous connections resulting in different hydraulic responses to recharge and different concentrations of weathering solutes. To test this hypothesis, we combined modeling and field approaches. We modeled weathering solutes along the hypothesized flow paths using PFLOTRAN. We measured hydrologic gradients in the hillslopes and riparian zone using piezometer water levels. We collected geochemical data including major ions and silica. Weathering solute concentrations were measured directly in the precipitation, hillslope springs, and the riparian zone for comparison to modeled concentration values. End member mixing methods were used to determine contributions of precipitation, hillslopes, and riparian zone to the stream. Combining geophysical, geochemical, and hydrological methods may offer insights into the source of stream water and controls on chemical weathering. Previous hypotheses that Piedmont critical zone architecture results from a balance of erosion, soil, and weathering front advance rates cannot account for the inverted regolith structure observed through seismic investigations at Pond Branch. Recent alternative hypotheses including weathering along tectonically-induced fractures and weathering front advance have been proposed, but additional data are needed to test them. Developing a thorough, nuanced understanding of the geochemical and hydrological behavior of Pond Branch may help test and refine hypotheses for Piedmont critical zone evolution.

Tropical flowering phenologies

NASA Astrophysics Data System (ADS)

Wright, S. J.

2016-12-01

Most tropical plants flower synchronously at species-specific times. This holds at the geographic equator where day length is constant and at the meteorological equator where temperature is virtually aseasonal. Thus, the well-studied environmental cues for flowering at higher latitudes can be irrelevant in the tropics where they are replaced by an abundance of hypotheses. Low and high temperatures, drought and rain, day length, daily solar irradiance, and seasonal changes in solar insolation at the forest canopy or at the top of the atmosphere have all been hypothesized to act as environmental cues for tropical flowering. This abundance of hypotheses has been confronted by a paucity of data, precluding rejection of even one hypothesis. I will use new long-term data sets from Barro Colorado Island (BCI), Panama (9°N, 79°W) and a model selection framework to begin the winnowing. The data extend from 1987 to the present and include more than 250,000 flower records obtained in 1,515 weekly censuses of 200 passive traps and standard meteorological variables obtained just above the forest canopy. The model selection framework was used to evaluate every proximate cue hypothesized to control tropical flowering times for the 55 tree and liana species best represented in the data. Hypotheses concerning seasonal variation in day length, temperature, rainfall and photosynthetically active radiation (PAR) best matched the data for five, zero, seven and 32 species, respectively. Many species previously believed to respond to seasonal changes in moisture availability are actually sensitive to seasonal variation in cloud cover and PAR. BCI lies on the meteorological equator, thus it is unsurprising that temperature variation is not a viable proximate cue. The flowering phenology of the remaining 11 species could not be explained by any of the hypothesized proximate cues. Solutions to the environmental control of tropical flowering times remain to be discovered.

Be a good loser: A theoretical model for subordinate decision-making on bi-directional sex change in haremic fishes.

PubMed

Sawada, Kota; Yamaguchi, Sachi; Iwasa, Yoh

2017-05-21

Among animals living in groups with reproductive skew associated with a dominance hierarchy, subordinates may do best by using various alternative tactics. Sequential hermaphrodites or sex changers adopt a unique solution, that is, being the sex with weaker skew when they are small and subordinate, and changing sex when they become larger. In bi-directionally sex-changing fishes, although most are haremic and basically protogynous, subordinate males can change sex to being females. We study a mathematical model to examine when and why such reversed sex change is more adaptive than dispersal to take over another harem. We attempt to examine previously proposed hypotheses that the risk of dispersal and low density favor reversed sex change, and to specify an optimal decision-making strategy for subordinates. As a result, while the size-dependent conditional strategy in which smaller males tend to change sex is predicted, even large males are predicted to change sex under low density and/or high risk of dispersal, supporting both previous hypotheses. The importance of spatiotemporal variation of social and ecological conditions is also suggested. We discuss a unified framework to understand hermaphroditic and gonochoristic societies. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bidirectional associations between binge eating and restriction in anorexia nervosa. An ecological momentary assessment study☆

PubMed Central

De Young, Kyle P.; Lavender, Jason M.; Crosby, Ross D.; Wonderlich, Stephen A.; Engel, Scott G.; Mitchell, James E.; Crow, Scott J.; Peterson, Carol B.; Le Grange, Daniel

2014-01-01

This study examined the association between restrictive eating behaviors and binge eating in anorexia nervosa (AN) using data collected in the natural environment. Women (N = 118) with DSM-IV full or sub-threshold AN reported eating disorder behaviors, including binge eating episodes, going ≥ 8 waking hours without eating, and skipping meals, during 2 weeks of ecological momentary assessment (EMA). Time-lagged generalized estimating equations tested the following hypotheses: 1) dietary restriction would predict binge eating while controlling for binge eating the previous day; 2) binge eating would predict restriction the subsequent day while controlling for restriction the previous day. After controlling for relevant covariates, the hypotheses were not supported; however, there appeared to be a cumulative effect of repeatedly going 8 consecutive hours without eating (i.e. fasting) on the risk of binge eating among individuals who recently engaged in binge eating. In addition, skipping meals was associated with a lower risk of same day binge eating. The relationship between binge eating and dietary restriction appears to be complex and may vary by type of restrictive eating behavior. Future research should aim to further clarify the nature of the interaction of binge eating and restrictive eating among individuals with AN in order to effectively eliminate these behaviors in treatment. PMID:25134738

Legacies of precipitation fluctuations on primary production: theory and data synthesis.

PubMed

Sala, Osvaldo E; Gherardi, Laureano A; Reichmann, Lara; Jobbágy, Esteban; Peters, Debra

2012-11-19

Variability of above-ground net primary production (ANPP) of arid to sub-humid ecosystems displays a closer association with precipitation when considered across space (based on multiyear averages for different locations) than through time (based on year-to-year change at single locations). Here, we propose a theory of controls of ANPP based on four hypotheses about legacies of wet and dry years that explains space versus time differences in ANPP-precipitation relationships. We tested the hypotheses using 16 long-term series of ANPP. We found that legacies revealed by the association of current- versus previous-year conditions through the temporal series occur across all ecosystem types from deserts to mesic grasslands. Therefore, previous-year precipitation and ANPP control a significant fraction of current-year production. We developed unified models for the controls of ANPP through space and time. The relative importance of current-versus previous-year precipitation changes along a gradient of mean annual precipitation with the importance of current-year PPT decreasing, whereas the importance of previous-year PPT remains constant as mean annual precipitation increases. Finally, our results suggest that ANPP will respond to climate-change-driven alterations in water availability and, more importantly, that the magnitude of the response will increase with time.

Mimological Reveries? Disconfirming the Hypothesis of Phono-Emotional Iconicity in Poetry

PubMed Central

Kraxenberger, Maria; Menninghaus, Winfried

2016-01-01

The present study retested previously reported empirical evidence suggesting an iconic relation between sound and emotional meaning in poetry. To this end, we analyzed the frequency of certain phoneme classes in 48 German poems and correlated them with ratings for emotional classification. Our analyses provide evidence for a link between the emotional classification of poems (joyful vs. sad) and the perception of tonal contrast as reflected in the attribution of phenomenological sound qualia (bright vs. dark). However, we could not confirm any of the previous hypotheses and findings regarding either a connection between the frequencies of occurrence of specific vowel classes and the perception of tonal contrast, or a relation between the frequencies of occurrence of consonant classes and emotional classification. PMID:27895614

Pupillary Responses to Robotic and Human Emotions: The Uncanny Valley and Media Equation Confirmed.

PubMed

Reuten, Anne; van Dam, Maureen; Naber, Marnix

2018-01-01

Physiological responses during human-robots interaction are useful alternatives to subjective measures of uncanny feelings for nearly humanlike robots (uncanny valley) and comparable emotional responses between humans and robots (media equation). However, no studies have employed the easily accessible measure of pupillometry to confirm the uncanny valley and media equation hypotheses, evidence in favor of the existence of these hypotheses in interaction with emotional robots is scarce, and previous studies have not controlled for low level image statistics across robot appearances. We therefore recorded pupil size of 40 participants that viewed and rated pictures of robotic and human faces that expressed a variety of basic emotions. The robotic faces varied along the dimension of human likeness from cartoonish to humanlike. We strictly controlled for confounding factors by removing backgrounds, hair, and color, and by equalizing low level image statistics. After the presentation phase, participants indicated to what extent the robots appeared uncanny and humanlike, and whether they could imagine social interaction with the robots in real life situations. The results show that robots rated as nearly humanlike scored higher on uncanniness, scored lower on imagined social interaction, evoked weaker pupil dilations, and their emotional expressions were more difficult to recognize. Pupils dilated most strongly to negative expressions and the pattern of pupil responses across emotions was highly similar between robot and human stimuli. These results highlight the usefulness of pupillometry in emotion studies and robot design by confirming the uncanny valley and media equation hypotheses.

Pupillary Responses to Robotic and Human Emotions: The Uncanny Valley and Media Equation Confirmed

PubMed Central

Reuten, Anne; van Dam, Maureen; Naber, Marnix

2018-01-01

Physiological responses during human–robots interaction are useful alternatives to subjective measures of uncanny feelings for nearly humanlike robots (uncanny valley) and comparable emotional responses between humans and robots (media equation). However, no studies have employed the easily accessible measure of pupillometry to confirm the uncanny valley and media equation hypotheses, evidence in favor of the existence of these hypotheses in interaction with emotional robots is scarce, and previous studies have not controlled for low level image statistics across robot appearances. We therefore recorded pupil size of 40 participants that viewed and rated pictures of robotic and human faces that expressed a variety of basic emotions. The robotic faces varied along the dimension of human likeness from cartoonish to humanlike. We strictly controlled for confounding factors by removing backgrounds, hair, and color, and by equalizing low level image statistics. After the presentation phase, participants indicated to what extent the robots appeared uncanny and humanlike, and whether they could imagine social interaction with the robots in real life situations. The results show that robots rated as nearly humanlike scored higher on uncanniness, scored lower on imagined social interaction, evoked weaker pupil dilations, and their emotional expressions were more difficult to recognize. Pupils dilated most strongly to negative expressions and the pattern of pupil responses across emotions was highly similar between robot and human stimuli. These results highlight the usefulness of pupillometry in emotion studies and robot design by confirming the uncanny valley and media equation hypotheses. PMID:29875722

Testing the bi-dimensional effects of attitudes on behavioural intentions and subsequent behaviour.

PubMed

Elliott, Mark A; Brewster, Sarah E; Thomson, James A; Malcolm, Carly; Rasmussen, Susan

2015-11-01

Attitudes are typically treated as unidimensional predictors of both behavioural intentions and subsequent behaviour. On the basis of previous research showing that attitudes comprise two independent, positive and negative dimensions, we hypothesized that attitudes would be bi-dimensional predictors of both behavioural intentions and subsequent behaviour. We focused on health-risk behaviours. We therefore also hypothesized that the positive dimension of attitude (evaluations of positive behavioural outcomes) would better predict both behavioural intentions and subsequent behaviour than would the negative dimension, consistent with the positivity bias/offset principle. In Study 1 (cross sectional design), N = 109 university students completed questionnaire measures of their intentions to binge-drink and the positive and negative dimensions of attitude. Consistent with the hypotheses, both attitude dimensions independently predicted behavioural intentions and the positive dimension was a significantly better predictor than was the negative dimension. The same pattern of findings emerged in Study 2 (cross sectional design; N = 186 university students) when we predicted intentions to binge-drink, smoke and consume a high-fat diet. Similarly, in Study 3 (prospective design; N = 1,232 speed limit offenders), both the positive and negative dimensions of attitude predicted subsequent (6-month post-baseline) speeding behaviour on two different road types and the positive dimension was the better predictor. The implications for understanding the motivation of behaviour and the development of behaviour-change interventions are discussed. © 2014 The British Psychological Society.

“These Are Just Stories, Mulder”: Exposure to Conspiracist Fiction Does Not Produce Narrative Persuasion

PubMed Central

Nera, Kenzo; Pantazi, Myrto; Klein, Olivier

2018-01-01

Narrative persuasion, i.e., the impact of narratives on beliefs, behaviors and attitudes, and the mechanisms underpinning endorsement of conspiracy theories have both drawn substantial attention from social scientists. Yet, to date, these two fields have evolved separately, and to our knowledge no study has empirically examined the impact of conspiracy narratives on real-world conspiracy beliefs. In a first study, we exposed a group of participants (n = 37) to an X-Files episode before asking them to fill in a questionnaire related to their narrative experience and conspiracy beliefs. A control group (n = 41) had to answer the conspiracy beliefs items before watching the episode. Based on past findings of both the aforementioned fields of research, we hypothesized that the experimental group would show greater endorsement of conspiracy beliefs, an effect expected to be mediated by identification to the episodes' characters. We furthermore hypothesized that identification would be associated with cognitive elaboration of the topics developed in the narrative. The first two hypotheses were disproved since no narrative persuasion effect was observed. In a second study, we sought to replicate these results in a larger sample (n = 166). No persuasive effect was found in the new data and a Bayesian meta-analysis of the two studies strongly supports the absence of a positive effect of exposure to narrative material on endorsement of conspiracy theories. In both studies, a significant relation between conspiracy mentality and enjoyment was observed. In the second study, this relation was fully mediated by two dimensions of perceived realism, i.e., plausibility and narrative consistency. We discuss our results, based on theoretical models of narrative persuasion and compare our studies with previous narrative persuasion studies. Implications of these results for future research are also discussed. PMID:29875710

"These Are Just Stories, Mulder": Exposure to Conspiracist Fiction Does Not Produce Narrative Persuasion.

PubMed

Nera, Kenzo; Pantazi, Myrto; Klein, Olivier

2018-01-01

Narrative persuasion, i.e., the impact of narratives on beliefs, behaviors and attitudes, and the mechanisms underpinning endorsement of conspiracy theories have both drawn substantial attention from social scientists. Yet, to date, these two fields have evolved separately, and to our knowledge no study has empirically examined the impact of conspiracy narratives on real-world conspiracy beliefs. In a first study, we exposed a group of participants ( n = 37) to an X-Files episode before asking them to fill in a questionnaire related to their narrative experience and conspiracy beliefs. A control group ( n = 41) had to answer the conspiracy beliefs items before watching the episode. Based on past findings of both the aforementioned fields of research, we hypothesized that the experimental group would show greater endorsement of conspiracy beliefs, an effect expected to be mediated by identification to the episodes' characters. We furthermore hypothesized that identification would be associated with cognitive elaboration of the topics developed in the narrative. The first two hypotheses were disproved since no narrative persuasion effect was observed. In a second study, we sought to replicate these results in a larger sample ( n = 166). No persuasive effect was found in the new data and a Bayesian meta-analysis of the two studies strongly supports the absence of a positive effect of exposure to narrative material on endorsement of conspiracy theories. In both studies, a significant relation between conspiracy mentality and enjoyment was observed. In the second study, this relation was fully mediated by two dimensions of perceived realism, i.e., plausibility and narrative consistency. We discuss our results, based on theoretical models of narrative persuasion and compare our studies with previous narrative persuasion studies. Implications of these results for future research are also discussed.

Bases of social power, leadership styles, and organizational commitment.

PubMed

Pierro, Antonio; Raven, Bertram H; Amato, Clara; Bélanger, Jocelyn J

2013-01-01

Affective organizational commitment reflects the extent to which organizational members are loyal and willing to work toward organizational objectives (Meyer & Allen, 1997). In particular, affective organizational commitment holds very important implications at all organizational levels (e.g., turnover rates, performance, and citizenship behavior). Whereas previous research has evinced the positive influence of transformational and charismatic leadership styles on affective commitment toward the organization (Bass & Avolio, 1994), little is known with regard to the nature of this relationship. In line with the interpersonal power/interaction model, the present investigation aimed to investigate the mechanism at play between transformational leadership style and affective organizational commitment. Specifically, we hypothesized that transformational leadership style would increase affective organizational commitment through its effect on willingness to comply with soft bases of power. In two studies, we subjected the foregoing hypotheses to empirical scrutiny. In Study 1, the proposed mediation model was empirically supported with Italian employees in the public sector. Attesting to the robustness of our findings, Study 2 replicated the findings of Study 1 with Italian employees from the public and private sectors. In addition, Study 2 replicated Study 1 using a different measure of transformational leadership. Both Study 1 and Study 2 provided results consistent with our hypotheses. Specifically, the present paper reports empirical evidence that (1) the more participants report having a transformational leader, the more willing they become to comply with soft (but not harsh) power bases, (2) in turn, greater willingness to comply with soft (but not harsh) power bases increases one's affective organizational commitment. These findings provide additional support for the interpersonal power/interaction model and pave the way for new research directions.

Administrative Attribution Theory.

ERIC Educational Resources Information Center

Frasher, James M.; Frasher, Ramona S.

1981-01-01

Hypothesizes that the growing body of empirical data concerning attribution theory offers insight into the administrative process. To stimulate research to test this hypothesis, presents previous relevant research and a theory entitled Administrative Attribution Theory. Research questions applying the theory to educational administration are…

The evolution of social and semantic networks in epistemic communities

NASA Astrophysics Data System (ADS)

Margolin, Drew Berkley

This study describes and tests a model of scientific inquiry as an evolving, organizational phenomenon. Arguments are derived from organizational ecology and evolutionary theory. The empirical subject of study is an epistemic community of scientists publishing on a research topic in physics: the string theoretic concept of "D-branes." The study uses evolutionary theory as a means of predicting change in the way members of the community choose concepts to communicate acceptable knowledge claims. It is argued that the pursuit of new knowledge is risky, because the reliability of a novel knowledge claim cannot be verified until after substantial resources have been invested. Using arguments from both philosophy of science and organizational ecology, it is suggested that scientists can mitigate and sensibly share the risks of knowledge discovery within the community by articulating their claims in legitimate forms, i.e., forms that are testable within and relevant to the community. Evidence from empirical studies of semantic usage suggests that the legitimacy of a knowledge claim is influenced by the characteristics of the concepts in which it is articulated. A model of conceptual retention, variation, and selection is then proposed for predicting the usage of concepts and conceptual co-occurrences in the future publications of the community, based on its past. Results substantially supported hypothesized retention and selection mechanisms. Future concept usage was predictable from previous concept usage, but was limited by conceptual carrying capacity as predicted by density dependence theory. Also as predicted, retention was stronger when the community showed a more cohesive social structure. Similarly, concepts that showed structural signatures of high testability and relevance were more likely to be selected after previous usage frequency was controlled for. By contrast, hypotheses for variation mechanisms were not supported. Surprisingly, concepts whose structural position suggested they would be easiest to discover through search processes were used less frequently, once previous usage frequency was controlled for. The study also makes a theoretical contribution by suggesting ways that evolutionary theory can be used to integrate findings from the study of science with insights from organizational communication. A variety of concrete directions for future studies of social and semantic network evolution are also proposed.

Metatranscriptomic insights on gene expression and regulatory controls in Candidatus Accumulibacter phosphatis

DOE PAGES

Oyserman, Ben O.; Noguera, Daniel R.; del Rio, Tijana Glavina; ...

2015-11-10

Previous studies on enhanced biological phosphorus removal (EBPR) have focused on reconstructing genomic blueprints for the model polyphosphate-accumulating organism Candidatus Accumulibacter phosphatis. Here, a time series metatranscriptome generated from enrichment cultures of Accumulibacter was used to gain insight into anerobic/aerobic metabolism and regulatory mechanisms within an EBPR cycle. Co-expressed gene clusters were identified displaying ecologically relevant trends consistent with batch cycle phases. Transcripts displaying increased abundance during anerobic acetate contact were functionally enriched in energy production and conversion, including upregulation of both cytoplasmic and membrane-bound hydrogenases demonstrating the importance of transcriptional regulation to manage energy and electron flux during anerobicmore » acetate contact. We hypothesized and demonstrated hydrogen production after anerobic acetate contact, a previously unknown strategy for Accumulibacter to maintain redox balance. Genes involved in anerobic glycine utilization were identified and phosphorus release after anerobic glycine contact demonstrated, suggesting that Accumulibacter routes diverse carbon sources to acetyl-CoA formation via previously unrecognized pathways. A comparative genomics analysis of sequences upstream of co-expressed genes identified two statistically significant putative regulatory motifs. One palindromic motif was identified upstream of genes involved in PHA synthesis and acetate activation and is hypothesized to be a phaR binding site, hence representing a hypothetical PHA modulon. A second motif was identified ~35 base pairs (bp) upstream of a large and diverse array of genes and hence may represent a sigma factor binding site. As a result, this analysis provides a basis and framework for further investigations into Accumulibacter metabolism and the reconstruction of regulatory networks in uncultured organisms.« less

Metatranscriptomic insights on gene expression and regulatory controls in Candidatus Accumulibacter phosphatis

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

Oyserman, Ben O.; Noguera, Daniel R.; del Rio, Tijana Glavina

Previous studies on enhanced biological phosphorus removal (EBPR) have focused on reconstructing genomic blueprints for the model polyphosphate-accumulating organism Candidatus Accumulibacter phosphatis. Here, a time series metatranscriptome generated from enrichment cultures of Accumulibacter was used to gain insight into anerobic/aerobic metabolism and regulatory mechanisms within an EBPR cycle. Co-expressed gene clusters were identified displaying ecologically relevant trends consistent with batch cycle phases. Transcripts displaying increased abundance during anerobic acetate contact were functionally enriched in energy production and conversion, including upregulation of both cytoplasmic and membrane-bound hydrogenases demonstrating the importance of transcriptional regulation to manage energy and electron flux during anerobicmore » acetate contact. We hypothesized and demonstrated hydrogen production after anerobic acetate contact, a previously unknown strategy for Accumulibacter to maintain redox balance. Genes involved in anerobic glycine utilization were identified and phosphorus release after anerobic glycine contact demonstrated, suggesting that Accumulibacter routes diverse carbon sources to acetyl-CoA formation via previously unrecognized pathways. A comparative genomics analysis of sequences upstream of co-expressed genes identified two statistically significant putative regulatory motifs. One palindromic motif was identified upstream of genes involved in PHA synthesis and acetate activation and is hypothesized to be a phaR binding site, hence representing a hypothetical PHA modulon. A second motif was identified ~35 base pairs (bp) upstream of a large and diverse array of genes and hence may represent a sigma factor binding site. As a result, this analysis provides a basis and framework for further investigations into Accumulibacter metabolism and the reconstruction of regulatory networks in uncultured organisms.« less

Association of genetic variants in RAB23 and ANXA11 with uveitis in sarcoidosis

PubMed Central

Davoudi, Samaneh; Chang, Victoria S.; Navarro-Gomez, Daniel; Stanwyck, Lynn K.; Sevgi, Damla Duriye; Papavasileiou, Evangelia; Ren, Aiai; Uchiyama, Eduardo; Sullivan, Lynn; Lobo, Ann-Marie; Papaliodis, George N.

2018-01-01

Purpose Uveitis occurs in a subset of patients with sarcoidosis. The purpose of this study was to determine whether genetic variants that have been associated previously with overall sarcoidosis are associated with increased risk of developing uveitis. Methods Seventy-seven subjects were enrolled, including 45 patients diagnosed with sarcoidosis-related uveitis as cases and 32 patients with systemic sarcoidosis without ocular involvement as controls. Thirty-eight single nucleotide polymorphisms (SNPs) previously associated with sarcoidosis, sarcoidosis severity, or other organ-specific sarcoidosis involvement were identified. Allele frequencies in ocular sarcoidosis cases versus controls were compared using the chi-square test, and p values were corrected for multiple hypotheses testing using permutation. All analyses were conducted with PLINK. Results SNPs rs1040461 and rs61860052, in ras-related protein RAS23 (RAB23) and annexin A11 (ANXA11) genes, respectively, were associated with sarcoidosis-associated uveitis. The T allele of rs1040461 and the A allele of rs61860052 were found to be more prevalent in ocular sarcoidosis cases. These associations remained after correction for the multiple hypotheses tested (p=0.01 and p=0.02). In a subanalysis of Caucasian Americans only, two additional variants within the major histocompatibility complex (MHC) genes on chromosome 6, in HLA-DRB5 and HLA-DRB1, were associated with uveitis as well (p=0.009 and p=0.04). Conclusions Genetic variants in RAB23 and ANXA11 genes were associated with an increased risk of sarcoidosis-associated uveitis. These loci have previously been associated with overall sarcoidosis risk. PMID:29416296

Early Miocene hippopotamids (Cetartiodactyla) constrain the phylogenetic and spatiotemporal settings of hippopotamid origin

PubMed Central

Orliac, Maeva; Boisserie, Jean-Renaud; MacLatchy, Laura; Lihoreau, Fabrice

2010-01-01

The affinities of the Hippopotamidae are at the core of the phylogeny of Cetartiodactyla (even-toed mammals: cetaceans, ruminants, camels, suoids, and hippos). Molecular phylogenies support Cetacea as sister group of the Hippopotamidae, implying a long ghost lineage between the earliest cetaceans (∼53 Ma) and the earliest hippopotamids (∼16 Ma). Morphological studies have proposed two different sister taxa for hippopotamids: suoids (notably palaeochoerids) or anthracotheriids. Evaluating these phylogenetic hypotheses requires substantiating the poorly known early history of the Hippopotamidae. Here, we undertake an original morphological phylogenetic analysis including several “suiform” families and previously unexamined early Miocene taxa to test previous conflicting hypotheses. According to our results, Morotochoerus ugandensis and Kulutherium rusingensis, until now regarded as the sole African palaeochoerid and the sole African bunodont anthracotheriid, respectively, are unambiguously included within the Hippopotamidae. They are the earliest known hippopotamids and set the family fossil record back to the early Miocene (∼21 Ma). The analysis reveals that hippopotamids displayed an unsuspected taxonomic and body size diversity and remained restricted to Africa during most of their history, until the latest Miocene. Our results also confirm the deep nesting of Hippopotamidae within the paraphyletic Anthracotheriidae; this finding allows us to reconstruct the sequence of dental innovations that links advanced selenodont anthracotheriids to hippopotamids, previously a source of major disagreements on hippopotamid origins. The analysis demonstrates a close relationship between Eocene choeropotamids and anthracotheriids, a relationship that potentially fills the evolutionary gap between earliest hippopotamids and cetaceans implied by molecular analyses. PMID:20547829

Impact of liking for advertising and brand allegiance on drinking and alcohol-related aggression: a longitudinal study.

PubMed

Casswell, S; Zhang, J F

1998-08-01

To test a hypothesized model of the effect of televised alcohol advertising and allegiance to specific brands of beer on subsequent beer consumption and self-reports of aggressive behaviour linked with drinking. Structural equation modelling was used to assess the fit between data collected as part of a longitudinal study of young people's health and development and a hypothesized model based on theoretical perspectives and previous research. A birth cohort has been assessed every few years, most of them in their home city of Dunedin, New Zealand. The questions about alcohol are asked as part of the day-long assessment. Members of a longitudinal survey cohort at ages 18 and 21 years. Data from 630 beer drinking participants were analysed in this study. Responses to questions about beer consumption, liking for advertising, favourite brand of beer and self-reports of alcohol-related aggressive behaviour. Our hypothesized model assumed a positive impact of liking of alcohol advertising and brand allegiance at age 18 on the volume of beer consumed at age 21 and self-reports of alcohol-related aggressive behaviour. This was found to be a good fit to the data from the longitudinal study. This measurable impact of alcohol advertising occurred during a time of decline in aggregate alcohol in New Zealand. While this effect was not large enough to halt the decline in aggregate alcohol consumption it does indicate a measurable, specific impact of broadcast alcohol advertising on alcohol consumption and related behaviour which is of relevance for public health policy.

Acute lesions that impair affective empathy

PubMed Central

Oishi, Kenichi; Hsu, John; Lindquist, Martin; Gottesman, Rebecca F.; Jarso, Samson; Crainiceanu, Ciprian; Mori, Susumu

2013-01-01

Functional imaging studies of healthy participants and previous lesion studies have provided evidence that empathy involves dissociable cognitive functions that rely on at least partially distinct neural networks that can be individually impaired by brain damage. These studies converge in support of the proposal that affective empathy—making inferences about how another person feels—engages at least the following areas: prefrontal cortex, orbitofrontal gyrus, anterior insula, anterior cingulate cortex, temporal pole, amygdala and temporoparietal junction. We hypothesized that right-sided lesions to any one of these structures, except temporoparietal junction, would cause impaired affective empathy (whereas bilateral damage to temporoparietal junction would be required to disrupt empathy). We studied 27 patients with acute right hemisphere ischaemic stroke and 24 neurologically intact inpatients on a test of affective empathy. Acute impairment of affective empathy was associated with infarcts in the hypothesized network, particularly temporal pole and anterior insula. All patients with impaired affective empathy were also impaired in comprehension of affective prosody, but many patients with impairments in prosodic comprehension had spared affective empathy. Patients with impaired affective empathy were older, but showed no difference in performance on tests of hemispatial neglect, volume of infarct or sex distribution compared with patients with intact affective empathy. PMID:23824490

A cohort study evaluation of maternal PCB exposure related to time to pregnancy in daughters.

PubMed

Gennings, Chris; Carrico, Caroline; Factor-Litvak, Pam; Krigbaum, Nickilou; Cirillo, Piera M; Cohn, Barbara A

2013-08-20

Polychlorinated biphenyls (PCBs) remain ubiquitous environmental contaminants. Developmental exposures are suspected to impact reproduction. Analysis of mixtures of PCBs may be problematic as components have a complex correlation structure, and along with limited sample sizes, standard regression strategies are problematic. We compared the results of a novel, empirical method to those based on categorization of PCB compounds by (1) hypothesized biological activity previously proposed and widely applied, and (2) degree of ortho- substitution (mono, di, tri), in a study of the relation of maternal serum PCBs and daughter's time to pregnancy. We measured PCBs in maternal serum samples collected in the early postpartum in 289 daughters in the Child Health and Development Studies birth cohort. We queried time to pregnancy in these daughters 28-31 years later. We applied a novel weighted quantile sum approach to find the bad-actor compounds in the PCB mixture found in maternal serum. The approach includes empirical estimation of the weights through a bootstrap step which accounts for the variation in the estimated weights. Bootstrap analyses indicated the dominant functionality groups associated with longer TTP were the dioxin-like, anti-estrogenic group (average weight, 22%) and PCBs not previously classified by biological activity (54%). In contrast, the unclassified PCBs were not important in the association with shorter TTP, where the anti-estrogenic groups and the PB-inducers group played a more important role (60% and 23%, respectively). The highly chlorinated PCBs (average weight, 89%) were mostly associated with longer TTP; in contrast, the degree of chlorination was less discriminating for shorter TTP. Finally, PCB 56 was associated with the strongest relationship with TTP with a weight of 47%. Our empirical approach found some associations previously identified by two classification schemes, but also identified other bad actors. This empirical method can generate hypotheses about mixture effects and mechanisms and overcomes some of the limitations of standard regression techniques.

Relations between isoprene and nitric oxide in exhaled breath and the potential influence of outdoor ozone: a pilot study

PubMed Central

Khan, Alya; Staimer, Norbert; Tjoa, Thomas; Galassetti, Pietro; Blake, Donald R.; Delfino, Ralph J.

2013-01-01

The role of endogenous isoprene in the human body, if any, is unclear because previous research is inconsistent and mechanistic evidence for the biologic function of isoprene is lacking. Given previous evidence that exhaled isoprene is elevated in systemic inflammatory states, we hypothesized that exhaled isoprene would be positively associated with a breath biomarker of airway inflammation, the fractional concentration of exhaled nitric oxide (FENO). We examined relationships of exhaled breath isoprene with FENO and with outdoor ozone given that ozone chemically reacts with isoprene and has been positively associated with FENO in past studies. Sixteen elderly subjects were followed with ≤12 weekly exhaled hydrocarbon and FENO collections at the subjects’ retirement community. Outdoor ozone concentrations were measured continuously on site. Mixed-effects regression analyses tested relations of FENO with isoprene, and FENO and isoprene with ozone, adjusted for temperature. We found FENO was inversely associated with isoprene, and this was not confounded by ozone. Isoprene was inversely related to ozone. FENO was positively related to ozone and this relation was not confounded by isoprene. In contrast to hypothesized relations, we conclude that exhaled isoprene is inversely associated with FENO as well as outdoor ozone, which suggests possible protective ozone-scavenging functions of endogenous isoprene. Findings may indicate chemical reactions of isoprene oxidation by ozone and by hydroxyl radicals in the presence of O2 that is dependent on NO concentration. These preliminary results need to be confirmed in additional studies of human subjects, particularly as they apply to FENO monitoring in asthma. PMID:23999846

Relations between isoprene and nitric oxide in exhaled breath and the potential influence of outdoor ozone: a pilot study.

PubMed

Khan, Alya; Staimer, Norbert; Tjoa, Thomas; Galassetti, Pietro; Blake, Donald R; Delfino, Ralph J

2013-09-01

The role of endogenous isoprene in the human body, if any, is unclear because previous research is inconsistent and mechanistic evidence for the biologic function of isoprene is lacking. Given previous evidence that exhaled isoprene is elevated in systemic inflammatory states, we hypothesized that exhaled isoprene would be positively associated with a breath biomarker of airway inflammation, the fractional concentration of exhaled nitric oxide (FENO). We examined relationships of exhaled breath isoprene with FENO and with outdoor ozone given that ozone chemically reacts with isoprene and has been positively associated with FENO in past studies. Sixteen elderly subjects were followed with ≤12 weekly exhaled hydrocarbon and FENO collections at the subjects' retirement community. Outdoor ozone concentrations were measured continuously on site. Mixed-effects regression analyses tested relations of FENO with isoprene, and FENO and isoprene with ozone, adjusted for temperature. We found FENO was inversely associated with isoprene, and this was not confounded by ozone. Isoprene was inversely related to ozone. FENO was positively related to ozone and this relation was not confounded by isoprene. In contrast to hypothesized relations, we conclude that exhaled isoprene is inversely associated with FENO as well as outdoor ozone, which suggests possible protective ozone-scavenging functions of endogenous isoprene. Findings may indicate chemical reactions of isoprene oxidation by ozone and by hydroxyl radicals in the presence of O2 that is dependent on NO concentration. These preliminary results need to be confirmed in additional studies of human subjects, particularly as they apply to FENO monitoring in asthma.

Rapid radiation in spiny lobsters (Palinurus spp) as revealed by classic and ABC methods using mtDNA and microsatellite data.

PubMed

Palero, Ferran; Lopes, Joao; Abelló, Pere; Macpherson, Enrique; Pascual, Marta; Beaumont, Mark A

2009-11-09

Molecular tools may help to uncover closely related and still diverging species from a wide variety of taxa and provide insight into the mechanisms, pace and geography of marine speciation. There is a certain controversy on the phylogeography and speciation modes of species-groups with an Eastern Atlantic-Western Indian Ocean distribution, with previous studies suggesting that older events (Miocene) and/or more recent (Pleistocene) oceanographic processes could have influenced the phylogeny of marine taxa. The spiny lobster genus Palinurus allows for testing among speciation hypotheses, since it has a particular distribution with two groups of three species each in the Northeastern Atlantic (P. elephas, P. mauritanicus and P. charlestoni) and Southeastern Atlantic and Southwestern Indian Oceans (P. gilchristi, P. delagoae and P. barbarae). In the present study, we obtain a more complete understanding of the phylogenetic relationships among these species through a combined dataset with both nuclear and mitochondrial markers, by testing alternative hypotheses on both the mutation rate and tree topology under the recently developed approximate Bayesian computation (ABC) methods. Our analyses support a North-to-South speciation pattern in Palinurus with all the South-African species forming a monophyletic clade nested within the Northern Hemisphere species. Coalescent-based ABC methods allowed us to reject the previously proposed hypothesis of a Middle Miocene speciation event related with the closure of the Tethyan Seaway. Instead, divergence times obtained for Palinurus species using the combined mtDNA-microsatellite dataset and standard mutation rates for mtDNA agree with known glaciation-related processes occurring during the last 2 my. The Palinurus speciation pattern is a typical example of a series of rapid speciation events occurring within a group, with very short branches separating different species. Our results support the hypothesis that recent climate change-related oceanographic processes have influenced the phylogeny of marine taxa, with most Palinurus species originating during the last two million years. The present study highlights the value of new coalescent-based statistical methods such as ABC for testing different speciation hypotheses using molecular data.

Semantically enabled and statistically supported biological hypothesis testing with tissue microarray databases

PubMed Central

2011-01-01

Background Although many biological databases are applying semantic web technologies, meaningful biological hypothesis testing cannot be easily achieved. Database-driven high throughput genomic hypothesis testing requires both of the capabilities of obtaining semantically relevant experimental data and of performing relevant statistical testing for the retrieved data. Tissue Microarray (TMA) data are semantically rich and contains many biologically important hypotheses waiting for high throughput conclusions. Methods An application-specific ontology was developed for managing TMA and DNA microarray databases by semantic web technologies. Data were represented as Resource Description Framework (RDF) according to the framework of the ontology. Applications for hypothesis testing (Xperanto-RDF) for TMA data were designed and implemented by (1) formulating the syntactic and semantic structures of the hypotheses derived from TMA experiments, (2) formulating SPARQLs to reflect the semantic structures of the hypotheses, and (3) performing statistical test with the result sets returned by the SPARQLs. Results When a user designs a hypothesis in Xperanto-RDF and submits it, the hypothesis can be tested against TMA experimental data stored in Xperanto-RDF. When we evaluated four previously validated hypotheses as an illustration, all the hypotheses were supported by Xperanto-RDF. Conclusions We demonstrated the utility of high throughput biological hypothesis testing. We believe that preliminary investigation before performing highly controlled experiment can be benefited. PMID:21342584

Statistical thermodynamics unveils the dissolution mechanism of cellobiose.

PubMed

Nicol, Thomas W J; Isobe, Noriyuki; Clark, James H; Shimizu, Seishi

2017-08-30

In the study of the cellulose dissolution mechanism opinion is still divided. Here, the solution interaction components of the most prominent hypotheses for the driving force of cellulose dissolution were evaluated quantitatively. Combining a rigorous statistical thermodynamic theory and cellobiose solubility data in the presence of chloride salts, whose cations progress in the Hofmeister series (KCl, NaCl, LiCl and ZnCl 2 ), we have shown that cellobiose solubilization is driven by the preferential accumulation of salts around the solutes which is stronger than cellobiose hydration. Yet contrary to the classical chaotropy hypothesis, increasing salt concentration leads to cellobiose dehydration in the presence of the strongest solubilizer ZnCl 2 . However, thanks to cellobiose dehydration, cellobiose-salt interaction still remains preferential despite weakening salt accumulation. Based on such insights, the previous hypotheses based on hydrophobicity and polymer charging have also been evaluated quantitatively. Thus, our present study successfully paved a way towards identifying the basic driving forces for cellulose solubilization in a quantitative manner for the first time. When combined with unit additivity methods this quantitative information could lead to a full understanding of cellulose solubility.

Evidence for kind representations in the absence of language: experiments with rhesus monkeys (Macaca mulatta).

PubMed

Phillips, Webb; Santos, Laurie R

2007-03-01

How do we come to recognize and represent different kinds of objects in the world? Some developmental psychologists have hypothesized that learning language plays a crucial role in this capacity. If this hypothesis were correct, then non-linguistic animals should lack the capacity to represent objects as kinds. Previous research with rhesus monkeys (Macaca mulatta) has shown that this species can successfully individuate different kinds of objects - monkeys who saw one kind of object hidden inside a box searched longer after finding a different kind of object. However, in these studies and the infant studies on which they were based, the objects to be individuated differed both in kind and in properties. Thus, subjects in these experiments may not be representing the kinds of objects per se, but instead only their immediate perceptual properties. Here, we show that rhesus monkeys successfully individuate different kinds of objects even when their perceptual properties are held constant. Although these data provide the best evidence to date that language is not necessary to represent kinds, we discuss our findings in terms of possible associative hypotheses as well.

Dependency, impulsivity, and self-harm: traits hypothesized to underlie the association between cluster B personality and substance use disorders.

PubMed

Casillas, Alex; Clark, Lee Anna

2002-10-01

Cluster B personality disorders (PDs) (i.e., antisocial, borderline, histrionic, and narcissistic) typically show a high degree of comorbidity with substance use disorders (SUDs). Previous research suggests that the broad-based personality domains of Disinhibition and Negative Temperament/Neuroticism may be common factors to both types of disorders. Using a two-phase process (i.e., screening and follow-up), this study examined three lower-order personality traits (i.e., dependency, impulsivity, and self-harm) that fall within the Disinhibition and Neuroticism domains. The study evaluated the hypotheses that these traits (a) are related both to cluster B PDs and to SUDs; and (b) underlie the association between the two types of disorders. Results indicate that impulsivity and self-harm play a significant role in cluster B PDs and SUDs, as well as in their association with each other. However, dependency was not associated with either type of disorder. These results indicate that sets of individual traits can be of significant utility in understanding the comorbidity between PDs and SUDs.

Life in the unthinking depths: energetic constraints on encephalization in marine fishes.

PubMed

Iglesias, T L; Dornburg, A; Brandley, M C; Alfaro, M E; Warren, D L

2015-05-01

Several hypotheses have been proposed to explain the limitation of brain size in vertebrates. Here, we test three hypotheses of brain size evolution using marine teleost fishes: the direct metabolic constraints hypothesis (DMCH), the expensive tissue hypothesis and the temperature-dependent hypothesis. Our analyses indicate that there is a robust positive correlation between encephalization and basal metabolic rate (BMR) that spans the full range of depths occupied by teleosts from the epipelagic (< 200 m), mesopelagic (200-1000 m) and bathypelagic (> 4000 m). Our results disentangle the effects of temperature and metabolic rate on teleost brain size evolution, supporting the DMCH. Our results agree with previous findings that teleost brain size decreases with depth; however, we also recover a negative correlation between trophic level and encephalization within the mesopelagic zone, a result that runs counter to the expectations of the expensive tissue hypothesis. We hypothesize that mesopelagic fishes at lower trophic levels may be investing more in neural tissue related to the detection of small prey items in a low-light environment. We recommend that comparative encephalization studies control for BMR in addition to controlling for body size and phylogeny. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

Assemblages of animals around urban structures: testing hypotheses of patterns in sediments under boat-mooring pontoons.

PubMed

Lindegarth, M

2001-05-01

Assemblages of animals in soft-sediments were studied in relation to pontoons for mooring private boats in two estuaries near Sydney, Australia. Based on previously observed patterns around other types of artificial structures, it was predicted that assemblages of animals under pontoons would be different from those in similar areas away from pontoons. Hypotheses about overall differences in average abundance and composition between sites with and without pontoons were tested, as were hypotheses about variable differences among and within estuaries. Analyses revealed that there were fewer crustaceans under pontoons in one estuary. The most conspicuous patterns related to pontoons were, however, differences in variability among sites with pontoons compared to sites without pontoons. Differences in spatial variability were found for the overall multivariate structure using Bray-Curtis dissimilarities and for abundances of most major taxa. Total abundance was approximately 60 times more variable among sites without pontoons and number of taxa were seven times more variable among sites with pontoons. Such patterns indicate that impacts of pontoons occur at some sites but not at others. This may be explained by intrinsic differences among sites or by differences in practices for maintenance. Predictions from these two contrasting models need to be tested in order to achieve efficient management of this type of structure.

Evolutionary origin and early biogeography of otophysan fishes (Ostariophysi: Teleostei).

PubMed

Chen, Wei-Jen; Lavoué, Sébastien; Mayden, Richard L

2013-08-01

The biogeography of the mega-diverse, freshwater, and globally distributed Otophysi has received considerable attention. This attraction largely stems from assumptions as to their ancient origin, the clade being almost exclusively freshwater, and their suitability as to explanations of trans-oceanic distributions. Despite multiple hypotheses explaining present-day distributions, problems remain, precluding more parsimonious explanations. Underlying previous hypotheses are alternative phylogenies for Otophysi, uncertainties as to temporal diversification and assumptions integral to various explanations. We reexamine the origin and early diversification of this clade based on a comprehensive time-calibrated, molecular-based phylogenetic analysis and event-based approaches for ancestral range inference of lineages. Our results do not corroborate current phylogenetic classifications of otophysans. We demonstrate Siluriformes are never sister to Gymnotiformes and Characiformes are most likely nonmonophyletic. Divergence time estimates specify a split between Cypriniformes and Characiphysi with the fragmentation of Pangea. The early diversification of characiphysans either predated, or was contemporary with, the separation of Africa and South America, and involved a combination of within- and between-continental divergence events for these lineages. The intercontinental diversification of siluroids and characoids postdated major intercontinental tectonic fragmentations (<90 Mya). Post-tectonic drift dispersal events are hypothesized to account for their current distribution patterns. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

Turning over a new 'leaf': multiple functional significances of leaves versus phyllodes in Hawaiian Acacia koa.

PubMed

Pasquet-Kok, Jessica; Creese, Christine; Sack, Lawren

2010-12-01

Hawaiian endemic tree Acacia koa is a model for heteroblasty with bipinnately compound leaves and phyllodes. Previous studies suggested three hypotheses for their functional differentiation: an advantage of leaves for early growth or shade tolerance, and an advantage of phyllodes for drought tolerance. We tested the ability of these hypotheses to explain differences between leaf types for potted plants in 104 physiological and morphological traits, including gas exchange, structure and composition, hydraulic conductance, and responses to varying light, intercellular CO(2) , vapour pressure deficit (VPD) and drought. Leaf types were similar in numerous traits including stomatal pore area per leaf area, leaf area-based gas exchange rates and cuticular conductance. Each hypothesis was directly supported by key differences in function. Leaves had higher mass-based gas exchange rates, while the water storage tissue in phyllodes contributed to greater capacitance per area; phyllodes also showed stronger stomatal closure at high VPD, and higher maximum hydraulic conductance per area, with stronger decline during desiccation and recovery with rehydration. While no single hypothesis completely explained the differences between leaf types, together the three hypotheses explained 91% of differences. These findings indicate that the heteroblasty confers multiple benefits, realized across different developmental stages and environmental contexts. © 2010 Blackwell Publishing Ltd.

Investigation of the Thermomechanical Response of Shape Memory Alloy Hybrid Composite Beams

NASA Technical Reports Server (NTRS)

Davis, Brian A.

2005-01-01

Previous work at NASA Langley Research Center (LaRC) involved fabrication and testing of composite beams with embedded, pre-strained shape memory alloy (SMA) ribbons. That study also provided comparison of experimental results with numerical predictions from a research code making use of a new thermoelastic model for shape memory alloy hybrid composite (SMAHC) structures. The previous work showed qualitative validation of the numerical model. However, deficiencies in the experimental-numerical correlation were noted and hypotheses for the discrepancies were given for further investigation. The goal of this work is to refine the experimental measurement and numerical modeling approaches in order to better understand the discrepancies, improve the correlation between prediction and measurement, and provide rigorous quantitative validation of the numerical model. Thermal buckling, post-buckling, and random responses to thermal and inertial (base acceleration) loads are studied. Excellent agreement is achieved between the predicted and measured results, thereby quantitatively validating the numerical tool.

Survival of bighorn sheep (Ovis canadensis) commingled with domestic sheep (Ovis aries) in the absence of Mycoplasma ovipneumoniae.

PubMed

Besser, Thomas E; Cassirer, E Frances; Yamada, Catherine; Potter, Kathleen A; Herndon, Caroline; Foreyt, William J; Knowles, Donald P; Srikumaran, Subramaniam

2012-01-01

To test the hypothesis that Mycoplasma ovipneumoniae is an important agent of the bighorn sheep (Ovis canadensis) pneumonia that has previously inevitably followed experimental commingling with domestic sheep (Ovis aries), we commingled M. ovipneumoniae-free domestic and bighorn sheep (n=4 each). One bighorn sheep died with acute pneumonia 90 days after commingling, but the other three remained healthy for >100 days. This unprecedented survival rate is significantly different (P=0.002) from that of previous bighorn-domestic sheep contact studies but similar to (P>0.05) bighorn sheep survival following commingling with other ungulates. The absence of epizootic respiratory disease in this experiment supports the hypothesized role of M. ovipneumoniae as a key pathogen of epizootic pneumonia in bighorn sheep commingled with domestic sheep.

Investigating the cognitive precursors of emotional response to cancer stress: re-testing Lazarus's transactional model.

PubMed

Hulbert-Williams, N J; Morrison, V; Wilkinson, C; Neal, R D

2013-02-01

Lazarus's Transactional Model of stress and coping underwent significant theoretical development through the 1990s to better incorporate emotional reactions to stress with their appraisal components. Few studies have robustly explored the full model. This study aimed to do so within the context of a major life event: cancer diagnosis. A repeated measures design was used whereby data were collected using self-report questionnaire at baseline (soon after diagnosis), and 3- and 6-month follow-up. A total of 160 recently diagnosed cancer patients were recruited (mean time since diagnosis = 46 days). Their mean age was 64.2 years. Data on appraisals, core-relational themes, and emotions were collected. Data were analysed using both Spearman's correlation tests and multivariate regression modelling. Longitudinal analysis demonstrated weak correlation between change scores of theoretically associated components and some emotions correlated more strongly with cognitions contradicting theoretical expectations. Cross-sectional multivariate testing of the ability of cognitions to explain variance in emotion was largely theory inconsistent. Although data support the generic structure of the Transactional Model, they question the model specifics. Larger scale research is needed encompassing a wider range of emotions and using more complex statistical testing. WHAT IS ALREADY KNOWN ON THIS SUBJECT?: • Stress processes are transactional and coping outcome is informed by both cognitive appraisal of the stressor and the individual's emotional response (Lazarus & Folkman, 1984). • Lazarus (1999) made specific hypotheses about which particular stress appraisals would determine which emotional response, but only a small number of these relationships have been robustly investigated. • Previous empirical testing of this theory has been limited by design and statistical limitations. WHAT DOES THIS STUDY ADD?: • This study empirically investigates the cognitive precedents of a much larger range of emotional outcomes than has previously been attempted in the literature. • Support for the model at a general level is established: this study demonstrates that both primary and secondary appraisals, and core-relational themes are important variables in explaining variance in emotional outcome. • The specific hypotheses proposed by Lazarus (1999) are not, however, supported: using data-driven approaches we demonstrate that equally high levels of variance can be explained using entirely different cognitive appraisals than those hypothesized. © 2012 The British Psychological Society.

Social comparison and perceived breach of psychological contract: their effects on burnout in a multigroup analysis.

PubMed

Cantisano, Gabriela Topa; Domínguez, J Francisco Morales; García, J Luis Caeiro

2007-05-01

This study focuses on the mediator role of social comparison in the relationship between perceived breach of psychological contract and burnout. A previous model showing the hypothesized effects of perceived breach on burnout, both direct and mediated, is proposed. The final model reached an optimal fit to the data and was confirmed through multigroup analysis using a sample of Spanish teachers (N = 401) belonging to preprimary, primary, and secondary schools. Multigroup analyses showed that the model fit all groups adequately.

A test of multiple hypotheses for the function of call sharing in female budgerigars, Melopsittacus undulatus

PubMed Central

Young, Anna M.; Cordier, Breanne; Mundry, Roger; Wright, Timothy F.

2014-01-01

In many social species group, members share acoustically similar calls. Functional hypotheses have been proposed for call sharing, but previous studies have been limited by an inability to distinguish among these hypotheses. We examined the function of vocal sharing in female budgerigars with a two-part experimental design that allowed us to distinguish between two functional hypotheses. The social association hypothesis proposes that shared calls help animals mediate affiliative and aggressive interactions, while the password hypothesis proposes that shared calls allow animals to distinguish group identity and exclude nonmembers. We also tested the labeling hypothesis, a mechanistic explanation which proposes that shared calls are used to address specific individuals within the sender–receiver relationship. We tested the social association hypothesis by creating four–member flocks of unfamiliar female budgerigars (Melopsittacus undulatus) and then monitoring the birds’ calls, social behaviors, and stress levels via fecal glucocorticoid metabolites. We tested the password hypothesis by moving immigrants into established social groups. To test the labeling hypothesis, we conducted additional recording sessions in which individuals were paired with different group members. The social association hypothesis was supported by the development of multiple shared call types in each cage and a correlation between the number of shared call types and the number of aggressive interactions between pairs of birds. We also found support for calls serving as a labeling mechanism using discriminant function analysis with a permutation procedure. Our results did not support the password hypothesis, as there was no difference in stress or directed behaviors between immigrant and control birds. PMID:24860236

Gene Function Hypotheses for the Campylobacter jejuni Glycome Generated by a Logic-Based Approach

PubMed Central

Sternberg, Michael J.E.; Tamaddoni-Nezhad, Alireza; Lesk, Victor I.; Kay, Emily; Hitchen, Paul G.; Cootes, Adrian; van Alphen, Lieke B.; Lamoureux, Marc P.; Jarrell, Harold C.; Rawlings, Christopher J.; Soo, Evelyn C.; Szymanski, Christine M.; Dell, Anne; Wren, Brendan W.; Muggleton, Stephen H.

2013-01-01

Increasingly, experimental data on biological systems are obtained from several sources and computational approaches are required to integrate this information and derive models for the function of the system. Here, we demonstrate the power of a logic-based machine learning approach to propose hypotheses for gene function integrating information from two diverse experimental approaches. Specifically, we use inductive logic programming that automatically proposes hypotheses explaining the empirical data with respect to logically encoded background knowledge. We study the capsular polysaccharide biosynthetic pathway of the major human gastrointestinal pathogen Campylobacter jejuni. We consider several key steps in the formation of capsular polysaccharide consisting of 15 genes of which 8 have assigned function, and we explore the extent to which functions can be hypothesised for the remaining 7. Two sources of experimental data provide the information for learning—the results of knockout experiments on the genes involved in capsule formation and the absence/presence of capsule genes in a multitude of strains of different serotypes. The machine learning uses the pathway structure as background knowledge. We propose assignments of specific genes to five previously unassigned reaction steps. For four of these steps, there was an unambiguous optimal assignment of gene to reaction, and to the fifth, there were three candidate genes. Several of these assignments were consistent with additional experimental results. We therefore show that the logic-based methodology provides a robust strategy to integrate results from different experimental approaches and propose hypotheses for the behaviour of a biological system. PMID:23103756

Gene function hypotheses for the Campylobacter jejuni glycome generated by a logic-based approach.

PubMed

Sternberg, Michael J E; Tamaddoni-Nezhad, Alireza; Lesk, Victor I; Kay, Emily; Hitchen, Paul G; Cootes, Adrian; van Alphen, Lieke B; Lamoureux, Marc P; Jarrell, Harold C; Rawlings, Christopher J; Soo, Evelyn C; Szymanski, Christine M; Dell, Anne; Wren, Brendan W; Muggleton, Stephen H

2013-01-09

Increasingly, experimental data on biological systems are obtained from several sources and computational approaches are required to integrate this information and derive models for the function of the system. Here, we demonstrate the power of a logic-based machine learning approach to propose hypotheses for gene function integrating information from two diverse experimental approaches. Specifically, we use inductive logic programming that automatically proposes hypotheses explaining the empirical data with respect to logically encoded background knowledge. We study the capsular polysaccharide biosynthetic pathway of the major human gastrointestinal pathogen Campylobacter jejuni. We consider several key steps in the formation of capsular polysaccharide consisting of 15 genes of which 8 have assigned function, and we explore the extent to which functions can be hypothesised for the remaining 7. Two sources of experimental data provide the information for learning-the results of knockout experiments on the genes involved in capsule formation and the absence/presence of capsule genes in a multitude of strains of different serotypes. The machine learning uses the pathway structure as background knowledge. We propose assignments of specific genes to five previously unassigned reaction steps. For four of these steps, there was an unambiguous optimal assignment of gene to reaction, and to the fifth, there were three candidate genes. Several of these assignments were consistent with additional experimental results. We therefore show that the logic-based methodology provides a robust strategy to integrate results from different experimental approaches and propose hypotheses for the behaviour of a biological system. Copyright © 2012 Elsevier Ltd. All rights reserved.

Mind wandering while reading easy and difficult texts.

PubMed

Feng, Shi; D'Mello, Sidney; Graesser, Arthur C

2013-06-01

Mind wandering is a phenomenon in which attention drifts away from the primary task to task-unrelated thoughts. Previous studies have used self-report methods to measure the frequency of mind wandering and its effects on task performance. Many of these studies have investigated mind wandering in simple perceptual and memory tasks, such as recognition memory, sustained attention, and choice reaction time tasks. Manipulations of task difficulty have revealed that mind wandering occurs more frequently in easy than in difficult conditions, but that it has a greater negative impact on performance in the difficult conditions. The goal of this study was to examine the relation between mind wandering and task difficulty in a high-level cognitive task, namely reading comprehension of standardized texts. We hypothesized that reading comprehension may yield a different relation between mind wandering and task difficulty than has been observed previously. Participants read easy or difficult versions of eight passages and then answered comprehension questions after reading each of the passages. Mind wandering was reported using the probe-caught method from several previous studies. In contrast to the previous results, but consistent with our hypothesis, mind wandering occurred more frequently when participants read difficult rather than easy texts. However, mind wandering had a more negative influence on comprehension for the difficult texts, which is consistent with the previous data. The results are interpreted from the perspectives of the executive-resources and control-failure theories of mind wandering, as well as with regard to situation models of text comprehension.

The Theory of Planned Behavior as a Model of Heavy Episodic Drinking Among College Students

PubMed Central

Collins, Susan E.; Carey, Kate B.

2008-01-01

This study provided a simultaneous, confirmatory test of the theory of planned behavior (TPB) in predicting heavy episodic drinking (HED) among college students. It was hypothesized that past HED, drinking attitudes, subjective norms and drinking refusal self-efficacy would predict intention, which would in turn predict future HED. Participants consisted of 131 college drinkers (63% female) who reported having engaged in HED in the previous two weeks. Participants were recruited and completed questionnaires within the context of a larger intervention study (see Collins & Carey, 2005). Latent factor structural equation modeling was used to test the ability of the TPB to predict HED. Chi-square tests and fit indices indicated good fit for the final structural models. Self-efficacy and attitudes but not subjective norms significantly predicted baseline intention, and intention and past HED predicted future HED. Contrary to hypotheses, however, a structural model excluding past HED provided a better fit than a model including it. Although further studies must be conducted before a definitive conclusion is reached, a TPB model excluding past behavior, which is arguably more parsimonious and theory driven, may provide better prediction of HED among college drinkers than a model including past behavior. PMID:18072832

Semantic priming effects in a lexical decision task: comparing third graders and college students in two different stimulus onset asynchronies.

PubMed

Holderbaum, Candice Steffen; de Salles, Jerusa Fumagalli

2011-11-01

Differences in the semantic priming effect comparing child and adult performance have been found by some studies. However, these differences are not well established, mostly because of the variety of methods used by researchers around the world. One of the main issues concerns the absence of semantic priming effects on children at stimulus onset asynchrony (SOA) smaller than 300ms. The aim of this study was to compare the semantic priming effect between third graders and college students at two different SOAs: 250ms and 500ms. Participants performed lexical decisions to targets which were preceded by semantic related or unrelated primes. Semantic priming effects were found at both SOAs in the third graders' group and in college students. Despite the fact that there was no difference between groups in the magnitude of semantic priming effects when SOA was 250ms, at the 500ms SOA their magnitude was bigger in children, corroborating previous studies. Hypotheses which could explain the presence of semantic priming effects in children's performance when SOA was 250ms are discussed, as well as hypotheses for the larger magnitude of semantic priming effects in children when SOA was 500ms.

The impact of receiving predictive genetic information about Lynch syndrome on individual colonoscopy and smoking behaviors

PubMed Central

Kim, Joanne Soo-Min; Coyte, Peter C.; Cotterchio, Michelle; Keogh, Louise A.; Flander, Louisa B.; Gaff, Clara; Laporte, Audrey

2016-01-01

Background This study investigated whether receiving the results of predictive genetic testing for Lynch syndrome—indicating the presence or absence of an inherited predisposition to various cancers, including colorectal cancer—was associated with change in individual colonoscopy and smoking behaviours, which could prevent colorectal cancer. Methods The study population included individuals with no previous diagnosis of colorectal cancer, whose families had already-identified deleterious mutations in the mismatch repair or EPCAM genes. Hypotheses were generated from a simple health economics model and tested against individual-level panel data from the Australasian Colorectal Cancer Family Registry. Results The empirical analysis revealed evidence consistent with some of the hypotheses, with a higher likelihood of undergoing colonoscopy in those who discovered their genetic predisposition to colorectal cancer and a lower likelihood of quitting smoking in those who discovered their lack thereof. Conclusion Predictive genetic information about Lynch syndrome was associated with change in individual colonoscopy and smoking behaviours but not necessarily in ways to improve population health. Impact The study findings suggest that the impact of personalized medicine on disease prevention is intricate, warranting further analyses to determine the net benefits and costs. PMID:27528600

The Role of Cuticular Pheromones in Courtship Conditioning of "Drosophila" Males

ERIC Educational Resources Information Center

Siwicki, Kathleen K.; Riccio, Paul; Ladewski, Lisa; Marcillac, Fabrice; Dartevelle, Laurence; Cross, Stephanie A.; Ferveur, Jean-Francois

2005-01-01

Courtship conditioning is an associative learning paradigm in "Drosophila melanogaster," wherein male courtship behavior is modified by experience with unreceptive, previously mated females. While the training experience with mated females involves multiple sensory and behavioral interactions, the authors hypothesized that female cuticular…

Self-Control and Deviant Peer Network Structure

ERIC Educational Resources Information Center

McGloin, Jean Marie; Shermer, Lauren O'Neill

2009-01-01

From learning and opportunity perspectives, peer group structural dimensions shed light on social processes that can amplify or ameliorate the risk of having delinquent friends. Previous research has not accounted for a primary criminological variable, self-control, limiting theoretical clarity. The authors developed three hypotheses about…

The Dispassionate Discourse of Children's Adjustment to Divorce.

ERIC Educational Resources Information Center

Allen, Katherine R.

1993-01-01

Responds to previous article by Amato on children's adjustment to divorce. Applauds Amato's efforts, but sees efforts hindered by insufficient reporting and inconsistent use of empirical literature, unsupported speculations about inconsistencies found in some hypotheses, and unacknowledged bias toward traditional family structure. Discusses many…

Beef heifers with diminished numbers of antral follicles have decreased uterine protein concentrations

USDA-ARS?s Scientific Manuscript database

Previous research demonstrated a favorable relationship between the number of follicles detectable in the bovine ovary by ultrasonography and fertility, and bovine females with diminished numbers of antral follicles had smaller reproductive tracts. Therefore, we hypothesized that uterine function w...

Examining the relationship between coping strategies and suicidal desire in a sample of United States military personnel.

PubMed

Khazem, Lauren R; Law, Keyne C; Green, Bradley A; Anestis, Michael D

2015-02-01

Suicidal desire in the military has been previously examined through the lens of the Interpersonal-Psychological Theory of Suicide (IPTS). However, no research has examined the impact of specific coping strategies on perceived burdensomeness, thwarted belongingness, and suicidal ideation in a large population of individuals serving in the US military. Furthermore, the factor structure of previously utilized coping clusters did not apply to our sample of military personnel. Therefore, we found a three-factor solution to be tested in this sample. We hypothesized that specific types of coping behavior clusters (Adaptive and Maladaptive) would predict both IPTS constructs and suicidal ideation. Results indicated that Adaptive and Maladaptive coping clusters predicted the IPTS constructs in the hypothesized directions. However, only the Maladaptive cluster predicted suicidal ideation. These findings implicate the need for further research and suicide prevention efforts focusing on coping strategies, specifically those that are maladaptive in nature, in relation to suicidal ideation in military members. Copyright © 2014 Elsevier Inc. All rights reserved.

A multiple hypotheses uncertainty analysis in hydrological modelling: about model structure, landscape parameterization, and numerical integration

NASA Astrophysics Data System (ADS)

Pilz, Tobias; Francke, Till; Bronstert, Axel

2016-04-01

Until today a large number of competing computer models has been developed to understand hydrological processes and to simulate and predict streamflow dynamics of rivers. This is primarily the result of a lack of a unified theory in catchment hydrology due to insufficient process understanding and uncertainties related to model development and application. Therefore, the goal of this study is to analyze the uncertainty structure of a process-based hydrological catchment model employing a multiple hypotheses approach. The study focuses on three major problems that have received only little attention in previous investigations. First, to estimate the impact of model structural uncertainty by employing several alternative representations for each simulated process. Second, explore the influence of landscape discretization and parameterization from multiple datasets and user decisions. Third, employ several numerical solvers for the integration of the governing ordinary differential equations to study the effect on simulation results. The generated ensemble of model hypotheses is then analyzed and the three sources of uncertainty compared against each other. To ensure consistency and comparability all model structures and numerical solvers are implemented within a single simulation environment. First results suggest that the selection of a sophisticated numerical solver for the differential equations positively affects simulation outcomes. However, already some simple and easy to implement explicit methods perform surprisingly well and need less computational efforts than more advanced but time consuming implicit techniques. There is general evidence that ambiguous and subjective user decisions form a major source of uncertainty and can greatly influence model development and application at all stages.

Relationship between oral health-related knowledge, attitudes and behavior among 15-16-year-old adolescents: a structural equation modeling approach.

PubMed

Tolvanen, Mimmi; Lahti, Satu; Miettunen, Jouko; Hausen, Hannu

2012-03-01

The aim of this study was to confirm the previously observed attitudinal factor structure related to behavioral change and the knowledge-attitude-behavior model on dental health and hygiene among adolescents. The study population consisted of all 8(th) and 9(th) graders (15-16 years) who started the 2004-2005 school year in Rauma, Finland (n = 827). Data on knowledge, attitudes, toothbrushing and using fluoride toothpaste were gathered by questionnaires. Hypothesized structure included four attitudinal factors related to dental health and hygiene: 'importance of toothbrushing when participating in social situations' (F1), 'importance of toothbrushing for health-related reasons and better appearance' (F2), 'being concerned about developing caries lesions' (F3) and 'importance of toothbrushing for feeling accepted' (F4). Structural equation modeling (SEM) was used to test the hypothesized model: pathways lead from knowledge to behavior both directly and via attitudes. The hypothesized model was also modified by removing non-significant pathways and studying the inter-relationships between attitudes. A confirmatory factor analysis revealed that factor F4 had to be removed. In the final model, knowledge influenced behavior directly and via two attitude factors, F1 and F2, which were inter-related. 'Concern about developing caries lesions' was a background factor influencing only knowledge. The final factor structure and SEM model were acceptable-to-good fit. Knowledge had a smaller effect on behavior than on attitudes. Our results support theories about the causal knowledge-attitudes-behavior chain, also for adolescents' oral health-related behaviors.

Self-critical perfectionism, daily stress, and disclosure of daily emotional events.

PubMed

Richardson, Clarissa M E; Rice, Kenneth G

2015-10-01

Although disclosure of stressful events can alleviate distress, self-critical perfectionism may pose an especially strong impediment to disclosure during stress, likely contributing to poorer psychological well-being. In the current study, after completing a measure of self-critical perfectionism (the Discrepancy subscale of the Almost Perfect Scale--Revised; Slaney, Rice, Mobley, Trippi, & Ashby, 2001), 396 undergraduates completed measures of stress and disclosure at the end of each day for 1 week. Consistent with hypotheses and previous research, multilevel modeling results indicated significant intraindividual coupling of daily stress and daily disclosure where disclosure was more likely when experiencing high stress than low stress. As hypothesized, Discrepancy moderated the relationship between daily stress and daily disclosure. Individuals higher in self-critical perfectionism (Discrepancy) were less likely to engage in disclosure under high stress, when disclosure is often most beneficial, than those with lower Discrepancy scores. These results have implications for understanding the role of stress and coping in the daily lives of self-critical perfectionists. (c) 2015 APA, all rights reserved).

Reducing Stigma and Punitive Attitudes Toward Pedophiles Through Narrative Humanization.

PubMed

Harper, Craig A; Bartels, Ross M; Hogue, Todd E

2016-12-01

Stigmatization and societal punitiveness about pedophilia have a range of potential consequences, such as the social isolation of people with sexual interest in children, and the formation of policies that are not consistent with empirical research findings. Previous research has shown that people with pedophilic sexual interests use societal thinking to self-stigmatize, which in turn may actually serve to increase their risk of committing a sexual offense. In this study, we compared two attitudinal interventions (first-person narrative vs. expert opinion) using a student sample ( N = 100). It was hypothesized that both interventions would lead to reductions in stigmatization and punitive attitudes about pedophiles on an explicit (self-report) level but that only the narrative intervention would lead to reductions of these constructs at the implicit level. Our findings supported both hypotheses. We further discuss the role of narrative humanization in this area and offer suggestions for further research based upon the theoretical and methodological implications of the findings.

Willingness to Share Research Data Is Related to the Strength of the Evidence and the Quality of Reporting of Statistical Results

PubMed Central

Wicherts, Jelte M.; Bakker, Marjan; Molenaar, Dylan

2011-01-01

Background The widespread reluctance to share published research data is often hypothesized to be due to the authors' fear that reanalysis may expose errors in their work or may produce conclusions that contradict their own. However, these hypotheses have not previously been studied systematically. Methods and Findings We related the reluctance to share research data for reanalysis to 1148 statistically significant results reported in 49 papers published in two major psychology journals. We found the reluctance to share data to be associated with weaker evidence (against the null hypothesis of no effect) and a higher prevalence of apparent errors in the reporting of statistical results. The unwillingness to share data was particularly clear when reporting errors had a bearing on statistical significance. Conclusions Our findings on the basis of psychological papers suggest that statistical results are particularly hard to verify when reanalysis is more likely to lead to contrasting conclusions. This highlights the importance of establishing mandatory data archiving policies. PMID:22073203

New U/Th ages for Pleistocene megafauna deposits of southeastern Queensland, Australia

NASA Astrophysics Data System (ADS)

Price, Gilbert J.; Zhao, Jian-xin; Feng, Yue-xing; Hocknull, Scott A.

2009-02-01

Arguments over the extinction of Pleistocene megafauna have become particularly polarised in recent years. Causes for the extinctions are widely debated with climate change, human hunting and/or habitat modification, or a combination of those factors, being the dominant hypotheses. However, a lack of a spatially constrained chronology for many megafauna renders most hypotheses difficult to test. Here, we present several new U/Th dates for a series of previously undated, megafauna-bearing localities from southeastern Queensland, Australia. The sites were previously used to argue for or against various megafauna extinction hypotheses, and are the type localities for two now-extinct Pleistocene marsupials (including the giant koala, Phascolarctos stirtoni). The new dating allows the deposits to be placed in a spatially- and temporally constrained context relevant to the understanding of Australian megafaunal extinctions. The results indicate that The Joint (Texas Caves) megafaunal assemblage is middle Pleistocene or older (>292 ky); the Cement Mills (Gore) megafaunal assemblage is late Pleistocene or older (>53 ky); and the Russenden Cave Bone Chamber (Texas Caves) megafaunal assemblage is late Pleistocene (˜55 ky). Importantly, the new results broadly show that the sites date prior to the hypothesised megafaunal extinction 'window' (i.e., ˜30-50 ky), and therefore, cannot be used to argue exclusively for or against human/climate change extinction models, without first exploring their palaeoecological significance on wider temporal and spatial scales.

Reverse engineering of logic-based differential equation models using a mixed-integer dynamic optimization approach

PubMed Central

Henriques, David; Rocha, Miguel; Saez-Rodriguez, Julio; Banga, Julio R.

2015-01-01

Motivation: Systems biology models can be used to test new hypotheses formulated on the basis of previous knowledge or new experimental data, contradictory with a previously existing model. New hypotheses often come in the shape of a set of possible regulatory mechanisms. This search is usually not limited to finding a single regulation link, but rather a combination of links subject to great uncertainty or no information about the kinetic parameters. Results: In this work, we combine a logic-based formalism, to describe all the possible regulatory structures for a given dynamic model of a pathway, with mixed-integer dynamic optimization (MIDO). This framework aims to simultaneously identify the regulatory structure (represented by binary parameters) and the real-valued parameters that are consistent with the available experimental data, resulting in a logic-based differential equation model. The alternative to this would be to perform real-valued parameter estimation for each possible model structure, which is not tractable for models of the size presented in this work. The performance of the method presented here is illustrated with several case studies: a synthetic pathway problem of signaling regulation, a two-component signal transduction pathway in bacterial homeostasis, and a signaling network in liver cancer cells. Supplementary information: Supplementary data are available at Bioinformatics online. Contact: julio@iim.csic.es or saezrodriguez@ebi.ac.uk PMID:26002881

Reverse engineering of logic-based differential equation models using a mixed-integer dynamic optimization approach.

PubMed

Henriques, David; Rocha, Miguel; Saez-Rodriguez, Julio; Banga, Julio R

2015-09-15

Systems biology models can be used to test new hypotheses formulated on the basis of previous knowledge or new experimental data, contradictory with a previously existing model. New hypotheses often come in the shape of a set of possible regulatory mechanisms. This search is usually not limited to finding a single regulation link, but rather a combination of links subject to great uncertainty or no information about the kinetic parameters. In this work, we combine a logic-based formalism, to describe all the possible regulatory structures for a given dynamic model of a pathway, with mixed-integer dynamic optimization (MIDO). This framework aims to simultaneously identify the regulatory structure (represented by binary parameters) and the real-valued parameters that are consistent with the available experimental data, resulting in a logic-based differential equation model. The alternative to this would be to perform real-valued parameter estimation for each possible model structure, which is not tractable for models of the size presented in this work. The performance of the method presented here is illustrated with several case studies: a synthetic pathway problem of signaling regulation, a two-component signal transduction pathway in bacterial homeostasis, and a signaling network in liver cancer cells. Supplementary data are available at Bioinformatics online. julio@iim.csic.es or saezrodriguez@ebi.ac.uk. © The Author 2015. Published by Oxford University Press.

Trimethylamine oxide accumulation as a function of depth in Hawaiian mid-water fishes

NASA Astrophysics Data System (ADS)

Bockus, Abigail B.; Seibel, Brad A.

2016-06-01

Trimethylamine oxide (TMAO) is a common osmolyte and counteracting solute. It is believed to combat the denaturation induced by hydrostatic pressure as some deep-sea animals contain higher TMAO levels than their shallow water counterparts. It has also been proposed that TMAO may accumulate passively during lipid storage resulting in a correlation between lipid content and TMAO levels in some groups. Previous research showed that lipid content decreased with depth in species of Hawaiian fishes presenting a novel test of these competing hypotheses. TMAO ranged from 20.4 to 92.8 mmol/kg. Lipid content ranged from 0.50 to 4.7% WW. After completing a comprehensive search for depths available in the literature, provided here, we analyzed TMAO and lipid as a function of average, minimum and maximum depth of occurrence for 27 species of fishes from nine orders. We found that TMAO is positively correlated with all measures of habitat depth (hydrostatic pressure) but the relationship is strongest with average depth. We further showed using phylogenetic independent contrasts that this relationship was not influenced by the evolutionary relatedness of these species. Interestingly, we found that lipid content increased with depth, in direct contrast to previous studies. TMAO is thus also positively correlated with lipid content. While we are unable to distinguish between these hypotheses, we show that TMAO is strongly correlated with depth in mid-water fishes.

Agroforestry management and phytoseiid communities in vineyards in the South of France.

PubMed

Liguori, Marialivia; Tixier, Marie-Stéphane; Hernandes, Akashi Fabio; Douin, Martial; Kreiter, Serge

2011-10-01

This study deals with the long-term effect of agroforestry management (trees within vine crops) on communities of phytoseiid mites. Several plots were considered: vineyards co-planted with Sorbus domestica or Pinus pinea, monocultures of vines and monocultures of S. domestica or P. pinea. All vine plots included two vine cultivars, Syrah and Grenache. Phytoseiid mites have been surveyed in these plots during several years within the previous 10 years. In 2010, samplings were again carried out in these same plots, from May to September, twice a month. Significantly higher densities of Phytoseiidae were observed on the cultivar Syrah (0.85 phytoseiids per leaf) than on Grenache (0.26 phytoseiids per leaf). Furthermore, significantly higher phytoseiid mite densities were observed in the monocultural grapevine plot than in the two co-planted ones. The main species found was Typhlodromus (Typhlodromus) exhilaratus in all vine plots considered. However, Kampimodromus aberrans was observed in the grapevine plots co-planted with the two trees, but never in the monocultural vine plot. Surprisingly, this phytoseiid species was not found on the co-planted trees, nor in the neighbouring uncultivated vegetation. Several hypotheses are discussed to explain such an unexpected distribution. Furthermore, contrary to what has been observed previously, agroforestry management did not seem to favour phytoseiid mite development, especially on the Grenache cultivar. Again, some hypotheses are developed to explain such observations and density modifications.

Thought Control Ability Is Different from Rumination in Explaining the Association between Neuroticism and Depression: A Three-Study Replication

PubMed Central

Lu, Feng-Ying; Yang, Wen-Jing; Zhang, Qing-Lin; Qiu, Jiang

2017-01-01

Neuroticism is the most common vulnerability factor of depression. However, the mechanism underlying this vulnerability is still unclear. Previous studies suggested that rumination intensifies the negative effect of neuroticism on depression. However, whether cognitive control could explain the association between neuroticism and depression remains unclear to date. Therefore, this study evaluated the indirect effects of rumination and thought control on the relationship between neuroticism and depression. Seven self-report measures were employed among healthy and main depression disorder (MDD) participants. Three studies were used to examine the hypotheses. Results of the three studies showed significant correlations among neuroticism, rumination, thought control, and depression. Rumination mediated the link between neuroticism and depression among healthy young adults, and this finding replicated previous studies. This study provided new evidence that thought control mediates the association between neuroticism and depression in both healthy and MDD populations. In conclusion, rumination increases neuroticism risk for depression, but high-level thought control decreases the effect of neuroticism on depression. This study may serve as a reference to develop effective and focused interventions for MDD patients. PMID:28620326

Beliefs about willpower moderate the effect of previous day demands on next day’s expectations and effective goal striving

PubMed Central

Bernecker, Katharina; Job, Veronika

2015-01-01

Research suggests that beliefs about willpower affect self-regulation following previous self-regulatory demands (Job et al., 2010). Some people believe that their willpower is limited, meaning that after a demanding task it needs to be replenished (limited theory). By contrast, others believe that willpower is not limited and that previous self-control tasks even activate willpower (non-limited theory). We hypothesized that when people experience a demanding day their beliefs about willpower predict their expected capacity to self-regulate and their actual self-regulation on the following day. In a daily diary study (N = 157), we measured students’ daily level of demands, their expected performance in unpleasant tasks, and their effective goal striving. Results showed that following a demanding day, students with a non-limited theory had higher expectations about their progress in unpleasant tasks and were striving more efficiently for their goals than students with a limited theory. These findings suggest that beliefs about willpower affect whether demands experienced on a previous day have positive or negative consequences on people’s self-regulation. PMID:26528198

Advances in the phylogenesis of Agaricales and its higher ranks and strategies for establishing phylogenetic hypotheses§

PubMed Central

Zhao, Rui-lin; Desjardin, Dennis E.; Soytong, Kasem; Hyde, Kevin D.

2008-01-01

We present an overview of previous research results on the molecular phylogenetic analyses in Agaricales and its higher ranks (Agaricomycetes/Agaricomycotina/Basidiomycota) along with the most recent treatments of taxonomic systems in these taxa. Establishing phylogenetic hypotheses using DNA sequences, from which an understanding of the natural evolutionary relationships amongst clades may be derived, requires a robust dataset. It has been recognized that single-gene phylogenies may not truly represent organismal phylogenies, but the concordant phylogenetic genealogies from multiple-gene datasets can resolve this problem. The genes commonly used in mushroom phylogenetic research are summarized. PMID:18837104

Stasis and convergence characterize morphological evolution in eupolypod II ferns.

PubMed

Sundue, Michael A; Rothfels, Carl J

2014-01-01

Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species. The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae - a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation.

Stasis and convergence characterize morphological evolution in eupolypod II ferns

PubMed Central

Sundue, Michael A.; Rothfels, Carl J.

2014-01-01

Background and Aims Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional ‘athyrioid’ ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Methods Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. Key Results The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of symplesiomorphic and homoplastic characters. Petiole vasculature consisting of two bundles is ancestral for eupolypods II and a synapomorphy for eupolypods II under deltran optimization. Sori restricted to one side of the vein defines the recently recognized clade comprising Rhachidosoraceae through Aspleniaceae, and sori present on both sides of the vein is a synapomorphy for the Athyriaceae sensu stricto. The results indicate that a chromosome base number of x =41 is synapomorphic for all eupolypods, a clade that includes over two-thirds of extant fern species. Conclusions The integrated approach synthesizes morphological studies with current phylogenetic hypotheses and provides explicit statements of character evolution in the eupolypod II fern families. Strong character support is found for previously recognized clades, whereas few characters support previously unrecognized clades. Sorus position appears to be less complicated than previously hypothesized, and linear sori restricted to one side of the vein support the clade comprising Aspleniaceae, Diplaziopsidaceae, Hemidictyaceae and Rachidosoraceae – a lineage only recently identified. Despite x =41 being a frequent number among extant species, to our knowledge it has not previously been demonstrated as the ancestral state. This is the first synapomorphy proposed for the eupolypod clade, a lineage comprising 67 % of extant fern species. This study provides some of the first hypotheses of character evolution at the family level and above in light of recent phylogenetic results, and promotes further study in an area that remains open for original observation. PMID:24197753

mHealth Visual Discovery Dashboard.

PubMed

Fang, Dezhi; Hohman, Fred; Polack, Peter; Sarker, Hillol; Kahng, Minsuk; Sharmin, Moushumi; al'Absi, Mustafa; Chau, Duen Horng

2017-09-01

We present Discovery Dashboard, a visual analytics system for exploring large volumes of time series data from mobile medical field studies. Discovery Dashboard offers interactive exploration tools and a data mining motif discovery algorithm to help researchers formulate hypotheses, discover trends and patterns, and ultimately gain a deeper understanding of their data. Discovery Dashboard emphasizes user freedom and flexibility during the data exploration process and enables researchers to do things previously challenging or impossible to do - in the web-browser and in real time. We demonstrate our system visualizing data from a mobile sensor study conducted at the University of Minnesota that included 52 participants who were trying to quit smoking.

mHealth Visual Discovery Dashboard

PubMed Central

Fang, Dezhi; Hohman, Fred; Polack, Peter; Sarker, Hillol; Kahng, Minsuk; Sharmin, Moushumi; al'Absi, Mustafa; Chau, Duen Horng

2018-01-01

We present Discovery Dashboard, a visual analytics system for exploring large volumes of time series data from mobile medical field studies. Discovery Dashboard offers interactive exploration tools and a data mining motif discovery algorithm to help researchers formulate hypotheses, discover trends and patterns, and ultimately gain a deeper understanding of their data. Discovery Dashboard emphasizes user freedom and flexibility during the data exploration process and enables researchers to do things previously challenging or impossible to do — in the web-browser and in real time. We demonstrate our system visualizing data from a mobile sensor study conducted at the University of Minnesota that included 52 participants who were trying to quit smoking. PMID:29354812

UV-B-Induced Erythema in Human Skin: The Circadian Clock Is Ticking.

PubMed

Sarkar, Soumyadeep; Gaddameedhi, Shobhan

2018-02-01

Acute exposure of skin to UV-B causes DNA damage and sunburn erythema in both mice and humans. Previous studies documented time-of-day-related differences in sunburn responses after UV-B exposure in mice. Because humans are diurnal and mice are nocturnal, the circadian rhythm in human skin was hypothesized to be in opposite phase to the rhythm in mice. A study by Nikkola et al. demonstrates that humans are more prone to sunburn erythema after evening exposure to solar UV-B radiation as compared with morning exposure. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Mycobacterium avium Subspecies paratuberculosis: Human Exposure through Environmental and Domestic Aerosols

PubMed Central

Rhodes, Glenn; Richardson, Hollian; Hermon-Taylor, John; Weightman, Andrew; Higham, Andrew; Pickup, Roger

2014-01-01

Mycobacterium avium subspecies paratuberculosis (Map) causes Johne’s disease in animals and is significantly associated with Crohn’s disease (CD) in humans. Our previous studies have shown Map to be present in U.K. rivers due to land deposition from chronic livestock infection and runoff driven by rainfall. The epidemiology of CD in Cardiff showed a significant association with the River Taff, in which Map can be detected on a regular basis. We have previously hypothesized that aerosols from the river might influence the epidemiology of CD. In this preliminary study, we detected Map by quantitative PCR in one of five aerosol samples collected above the River Taff. In addition, we examined domestic showers from different regions in the U.K. and detected Map in three out of 30 independent samples. In detecting Map in river aerosols and those from domestic showers, this is the first study to provide evidence that aerosols are an exposure route for Map to humans and may play a role in the epidemiology of CD. PMID:25438013

Repeat neurobehavioral study of borderline personality disorder.

PubMed Central

van Reekum, R; Links, P S; Finlayson, M A; Boyle, M; Boiago, I; Ostrander, L A; Moustacalis, E

1996-01-01

Previous research has tentatively identified a large subgroup of patients with borderline personality disorder (BPD) with histories of developmental or acquired brain insults. Similarly, these studies have demonstrated a possible biological correlation between the severity of BPD and the number of previous brain insults. The possibility of frontal system cognitive dysfunction in BPD has been raised. This single-blind, case-control study of BPD showed that 13 of 24 subjects with BPD had suffered a brain insult. Correlations between neurodevelopmental/acquired brain injury score and the diagnostic interview for borderline (DIB) score (r = 0.47), and between frontal system cognitive functioning and DIB score (r = -0.37) were seen. Neurocognitive testing and comparison with a cohort of subjects with traumatic brain injury (TBI) showed a pattern of similar cognitive functioning between the 2 groups, with the only differences on individual tests being in the direction of worse functioning in the group with BPD on 2 tasks. These results support the hypotheses described above. The main limitation reflects the low numbers of subjects. PMID:8580113

Appearance-Based First Impressions and Person Memory

ERIC Educational Resources Information Center

Bell, Raoul; Mieth, Laura; Buchner, Axel

2015-01-01

Previous research has demonstrated that people preferentially remember reputational information that is emotionally incongruent to their expectations, but it has left open the question of the generality of this effect. Three conflicting hypotheses were proposed: (a) The effect is restricted to information relevant to reciprocal social exchange.…

Methylphenidate Amplifies Long-Term Plasticity in the Hippocampus via Noradrenergic Mechanisms

ERIC Educational Resources Information Center

Dommett, Eleanor J.; Henderson, Emma L.; Westwell, Martin S.; Greenfield, Susan A.

2008-01-01

Methylphenidate treatment is used for Attention Deficit Hyperactivity Disorder and can improve learning and memory. Previously, improvements were considered a by-product of increased attention; however, we hypothesize that methylphenidate directly alters mechanisms underlying learning and memory, and therefore examined its effects on hippocampal…

Phylogenetic Interrelationships of Ginglymodian Fishes (Actinopterygii: Neopterygii)

PubMed Central

López-Arbarello, Adriana

2012-01-01

The Ginglymodi is one of the most common, though poorly understood groups of neopterygians, which includes gars, macrosemiiforms, and “semionotiforms.” In particular, the phylogenetic relationships between the widely distributed “semionotiforms,” and between them and other ginglymodians have been enigmatic. Here, the phylogenetic relationships between eight of the 11 “semionotiform” genera, five genera of living and fossil gars and three macrosemiid genera, are analysed through cladistic analysis, based on 90 morphological characters and 37 taxa, including 7 out-group taxa. The results of the analysis show that the Ginglymodi includes two main lineages: Lepisosteiformes and †Semionotiformes. The genera †Pliodetes, †Araripelepidotes, †Lepidotes, †Scheenstia, and †Isanichthys are lepisosteiforms, and not semionotiforms, as previously thought, and these taxa extend the stratigraphic range of the lineage leading to gars back up to the Early Jurassic. A monophyletic †Lepidotes is restricted to the Early Jurassic species, whereas the strongly tritoral species previously referred to †Lepidotes are referred to †Scheenstia. Other species previously referred to †Lepidotes represent other genera or new taxa. The macrosemiids are well nested within semionotiforms, together with †Semionotidae, here restricted to †Semionotus, and a new family including †Callipurbeckia n. gen. minor (previously referred to †Lepidotes), †Macrosemimimus, †Tlayuamichin, †Paralepidotus, and †Semiolepis. Due to the numerous taxonomic changes needed according to the phylogenetic analysis, this article also includes formal taxonomic definitions and diagnoses for all generic and higher taxa, which are new or modified. The study of Mesozoic ginglymodians led to confirm Patterson’s observation that these fishes show morphological affinities with both halecomorphs and teleosts. Therefore, the compilation of large data sets including the Mesozoic ginglymodians and the re-evaluation of several hypotheses of homology are essential to test the hypotheses of the Halecostomi vs. the Holostei, which is one of the major topics in the evolution of Mesozoic vertebrates and the origin of modern fish faunas. PMID:22808031

Phylogenetic interrelationships of ginglymodian fishes (Actinopterygii: Neopterygii).

PubMed

López-Arbarello, Adriana

2012-01-01

The Ginglymodi is one of the most common, though poorly understood groups of neopterygians, which includes gars, macrosemiiforms, and "semionotiforms." In particular, the phylogenetic relationships between the widely distributed "semionotiforms," and between them and other ginglymodians have been enigmatic. Here, the phylogenetic relationships between eight of the 11 "semionotiform" genera, five genera of living and fossil gars and three macrosemiid genera, are analysed through cladistic analysis, based on 90 morphological characters and 37 taxa, including 7 out-group taxa. The results of the analysis show that the Ginglymodi includes two main lineages: Lepisosteiformes and †Semionotiformes. The genera †Pliodetes, †Araripelepidotes, †Lepidotes, †Scheenstia, and †Isanichthys are lepisosteiforms, and not semionotiforms, as previously thought, and these taxa extend the stratigraphic range of the lineage leading to gars back up to the Early Jurassic. A monophyletic †Lepidotes is restricted to the Early Jurassic species, whereas the strongly tritoral species previously referred to †Lepidotes are referred to †Scheenstia. Other species previously referred to †Lepidotes represent other genera or new taxa. The macrosemiids are well nested within semionotiforms, together with †Semionotidae, here restricted to †Semionotus, and a new family including †Callipurbeckia n. gen. minor (previously referred to †Lepidotes), †Macrosemimimus, †Tlayuamichin, †Paralepidotus, and †Semiolepis. Due to the numerous taxonomic changes needed according to the phylogenetic analysis, this article also includes formal taxonomic definitions and diagnoses for all generic and higher taxa, which are new or modified. The study of Mesozoic ginglymodians led to confirm Patterson's observation that these fishes show morphological affinities with both halecomorphs and teleosts. Therefore, the compilation of large data sets including the Mesozoic ginglymodians and the re-evaluation of several hypotheses of homology are essential to test the hypotheses of the Halecostomi vs. the Holostei, which is one of the major topics in the evolution of Mesozoic vertebrates and the origin of modern fish faunas.

Using resource dependency theory to measure the environment in health care organizational studies: a systematic review of the literature.

PubMed

Yeager, Valerie A; Menachemi, Nir; Savage, Grant T; Ginter, Peter M; Sen, Bisakha P; Beitsch, Leslie M

2014-01-01

Studies using the resource dependency theory (RDT) perspective commonly focus on one or more of the following environmental dimensions: munificence, dynamism, and complexity. To date, no one has reviewed the use of this theory in the health care management literature and there exists no consensus on how to operationalize the market environment in health care settings. The purpose of this review is to examine and summarize the ways in which RDT has been applied in empirical studies of the external environments of health care organizations. In so doing, we identify gaps in the literature and examine the extent to which previous empirical findings aligned with hypothesized relationships based on RDT. We conducted a systematic review of the peer-reviewed literature using a bibliographic search of PubMed and ABI/Inform databases. To identify all health care studies that incorporated the RDT perspective, the words "healthcare" or "health care" were searched in combination with any of the following words: resource dependency theory, uncertainty perspective, environment, munificence, dynamism, and complexity. We also performed a hand search of the reference lists of all manuscripts identified in the initial search to identify additional articles. Twenty studies were included in this review. Wide variability existed in the number of variables used to measure the environment, the environmental constructs measured, and the specific variables used to operationalizethe environmental constructs. Of the 198 tests examining the relationship between environmental variables and the outcome of interest, 26.8% resulted in findings that supported the RDT-predicted hypotheses. The RDT literature is limited to studies of hospitals, nursing homes, and medical practices. There is little consensus on how to measure or operationalize the environment in these studies. No previous studies have measured the environment for other health care settings such as ambulatory surgery centers, public health departments, or assisted living facilities.

Metabolic mapping of the effects of the antidepressant fluoxetine on the brains of congenitally helpless rats.

PubMed

Shumake, Jason; Colorado, Rene A; Barrett, Douglas W; Gonzalez-Lima, F

2010-07-09

Antidepressants require adaptive brain changes before efficacy is achieved, and they may impact the affectively disordered brain differently than the normal brain. We previously demonstrated metabolic disturbances in limbic and cortical regions of the congenitally helpless rat, a model of susceptibility to affective disorder, and we wished to test whether administration of fluoxetine would normalize these metabolic differences. Fluoxetine was chosen because it has become a first-line drug for the treatment of affective disorders. We hypothesized that fluoxetine antidepressant effects may be mediated by decreasing metabolism in the habenula and increasing metabolism in the ventral tegmental area. We measured the effects of fluoxetine on forced swim behavior and regional brain cytochrome oxidase activity in congenitally helpless rats treated for 2 weeks with fluoxetine (5mg/kg, i.p., daily). Fluoxetine reduced immobility in the forced swim test as anticipated, but congenitally helpless rats responded in an atypical manner, i.e., increasing climbing without affecting swimming. As hypothesized, fluoxetine reduced metabolism in the habenula and increased metabolism in the ventral tegmental area. In addition, fluoxetine reduced the metabolism of the hippocampal dentate gyrus and dorsomedial prefrontal cortex. This study provided the first detailed mapping of the regional brain effects of an antidepressant drug in congenitally helpless rats. All of the effects were consistent with previous studies that have metabolically mapped the effects of serotonergic antidepressants in the normal rat brain, and were in the predicted direction of metabolic normalization of the congenitally helpless rat for all affected brain regions except the prefrontal cortex. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Evaluation of simple geochemical indicators of aeolian sand provenance: Late Quaternary dune fields of North America revisited

USGS Publications Warehouse

Muhs, Daniel

2017-01-01

Dune fields of Quaternary age occupy large areas of the world's arid and semiarid regions. Despite this, there has been surprisingly little work done on understanding dune sediment provenance, in part because many techniques are time-consuming, prone to operator error, experimental, highly specialized, expensive, or require sophisticated instrumentation. Provenance of dune sand using K/Rb and K/Ba values in K-feldspar in aeolian sands of the arid and semiarid regions of North America is tested here. Results indicate that K/Rb and K/Ba can distinguish different river sands that are sediment sources for dunes and dune fields themselves have distinctive K/Rb and K/Ba compositions. Over the Basin and Range and Great Plains regions of North America, the hypothesized sediment sources of dune fields are reviewed and assessed using K/Rb and K/Ba values in dune sands and in hypothesized source sediments. In some cases, the origins of dunes assessed in this manner are consistent with previous studies and in others, dune fields are found to have a more complex origin than previously thought. Use of K/Rb and K/Ba for provenance studies is a robust method that is inexpensive, rapid, and highly reproducible. It exploits one of the most common minerals found in dune sand, K-feldspar. The method avoids the problem of using simple concentrations of key elements that may be subject to interpretative bias due to changes in mineralogical maturity of Quaternary dune fields that occur over time.

Segmentation editing improves efficiency while reducing inter-expert variation and maintaining accuracy for normal brain tissues in the presence of space-occupying lesions

PubMed Central

Deeley, MA; Chen, A; Datteri, R; Noble, J; Cmelak, A; Donnelly, EF; Malcolm, A; Moretti, L; Jaboin, J; Niermann, K; Yang, Eddy S; Yu, David S; Dawant, BM

2013-01-01

Image segmentation has become a vital and often rate limiting step in modern radiotherapy treatment planning. In recent years the pace and scope of algorithm development, and even introduction into the clinic, have far exceeded evaluative studies. In this work we build upon our previous evaluation of a registration driven segmentation algorithm in the context of 8 expert raters and 20 patients who underwent radiotherapy for large space-occupying tumors in the brain. In this work we tested four hypotheses concerning the impact of manual segmentation editing in a randomized single-blinded study. We tested these hypotheses on the normal structures of the brainstem, optic chiasm, eyes and optic nerves using the Dice similarity coefficient, volume, and signed Euclidean distance error to evaluate the impact of editing on inter-rater variance and accuracy. Accuracy analyses relied on two simulated ground truth estimation methods: STAPLE and a novel implementation of probability maps. The experts were presented with automatic, their own, and their peers’ segmentations from our previous study to edit. We found, independent of source, editing reduced inter-rater variance while maintaining or improving accuracy and improving efficiency with at least 60% reduction in contouring time. In areas where raters performed poorly contouring from scratch, editing of the automatic segmentations reduced the prevalence of total anatomical miss from approximately 16% to 8% of the total slices contained within the ground truth estimations. These findings suggest that contour editing could be useful for consensus building such as in developing delineation standards, and that both automated methods and even perhaps less sophisticated atlases could improve efficiency, inter-rater variance, and accuracy. PMID:23685866

Effects of independently altering body weight and body mass on the metabolic cost of running.

PubMed

Teunissen, Lennart P J; Grabowski, Alena; Kram, Rodger

2007-12-01

The metabolic cost of running is substantial, despite the savings from elastic energy storage and return. Previous studies suggest that generating vertical force to support body weight and horizontal forces to brake and propel body mass are the major determinants of the metabolic cost of running. In the present study, we investigated how independently altering body weight and body mass affects the metabolic cost of running. Based on previous studies, we hypothesized that reducing body weight would decrease metabolic rate proportionally, and adding mass and weight would increase metabolic rate proportionally. Further, because previous studies show that adding mass alone does not affect the forces generated on the ground, we hypothesized that adding mass alone would have no substantial effect on metabolic rate. We manipulated the body weight and body mass of 10 recreational human runners and measured their metabolic rates while they ran at 3 m s(-1). We reduced weight using a harness system, increased mass and weight using lead worn about the waist, and increased mass alone using a combination of weight support and added load. We found that net metabolic rate decreased in less than direct proportion to reduced body weight, increased in slightly more than direct proportion to added load (added mass and weight), and was not substantially different from normal running with added mass alone. Adding mass alone was not an effective method for determining the metabolic cost attributable to braking/propelling body mass. Runners loaded with mass alone did not generate greater vertical or horizontal impulses and their metabolic costs did not substantially differ from those of normal running. Our results show that generating force to support body weight is the primary determinant of the metabolic cost of running. Extrapolating our reduced weight data to zero weight suggests that supporting body weight comprises at most 74% of the net cost of running. However, 74% is probably an overestimate of the metabolic demand of body weight to support itself because in reduced gravity conditions decrements in horizontal impulse accompanied decrements in vertical impulse.

Predictive Virtual Infection Modeling of Fungal Immune Evasion in Human Whole Blood.

PubMed

Prauße, Maria T E; Lehnert, Teresa; Timme, Sandra; Hünniger, Kerstin; Leonhardt, Ines; Kurzai, Oliver; Figge, Marc Thilo

2018-01-01

Bloodstream infections by the human-pathogenic fungi Candida albicans and Candida glabrata increasingly occur in hospitalized patients and are associated with high mortality rates. The early immune response against these fungi in human blood comprises a concerted action of humoral and cellular components of the innate immune system. Upon entering the blood, the majority of fungal cells will be eliminated by innate immune cells, i.e., neutrophils and monocytes. However, recent studies identified a population of fungal cells that can evade the immune response and thereby may disseminate and cause organ dissemination, which is frequently observed during candidemia. In this study, we investigate the so far unresolved mechanism of fungal immune evasion in human whole blood by testing hypotheses with the help of mathematical modeling. We use a previously established state-based virtual infection model for whole-blood infection with C. albicans to quantify the immune response and identified the fungal immune-evasion mechanism. While this process was assumed to be spontaneous in the previous model, we now hypothesize that the immune-evasion process is mediated by host factors and incorporate such a mechanism in the model. In particular, we propose, based on previous studies that the fungal immune-evasion mechanism could possibly arise through modification of the fungal surface by as of yet unknown proteins that are assumed to be secreted by activated neutrophils. To validate or reject any of the immune-evasion mechanisms, we compared the simulation of both immune-evasion models for different infection scenarios, i.e., infection of whole blood with either C. albicans or C. glabrata under non-neutropenic and neutropenic conditions. We found that under non-neutropenic conditions, both immune-evasion models fit the experimental data from whole-blood infection with C. albicans and C. glabrata . However, differences between the immune-evasion models could be observed for the infection outcome under neutropenic conditions with respect to the distribution of fungal cells across the immune cells. Based on these predictions, we suggested specific experimental studies that might allow for the validation or rejection of the proposed immune-evasion mechanism.

Predictive Virtual Infection Modeling of Fungal Immune Evasion in Human Whole Blood

PubMed Central

Prauße, Maria T. E.; Lehnert, Teresa; Timme, Sandra; Hünniger, Kerstin; Leonhardt, Ines; Kurzai, Oliver; Figge, Marc Thilo

2018-01-01

Bloodstream infections by the human-pathogenic fungi Candida albicans and Candida glabrata increasingly occur in hospitalized patients and are associated with high mortality rates. The early immune response against these fungi in human blood comprises a concerted action of humoral and cellular components of the innate immune system. Upon entering the blood, the majority of fungal cells will be eliminated by innate immune cells, i.e., neutrophils and monocytes. However, recent studies identified a population of fungal cells that can evade the immune response and thereby may disseminate and cause organ dissemination, which is frequently observed during candidemia. In this study, we investigate the so far unresolved mechanism of fungal immune evasion in human whole blood by testing hypotheses with the help of mathematical modeling. We use a previously established state-based virtual infection model for whole-blood infection with C. albicans to quantify the immune response and identified the fungal immune-evasion mechanism. While this process was assumed to be spontaneous in the previous model, we now hypothesize that the immune-evasion process is mediated by host factors and incorporate such a mechanism in the model. In particular, we propose, based on previous studies that the fungal immune-evasion mechanism could possibly arise through modification of the fungal surface by as of yet unknown proteins that are assumed to be secreted by activated neutrophils. To validate or reject any of the immune-evasion mechanisms, we compared the simulation of both immune-evasion models for different infection scenarios, i.e., infection of whole blood with either C. albicans or C. glabrata under non-neutropenic and neutropenic conditions. We found that under non-neutropenic conditions, both immune-evasion models fit the experimental data from whole-blood infection with C. albicans and C. glabrata. However, differences between the immune-evasion models could be observed for the infection outcome under neutropenic conditions with respect to the distribution of fungal cells across the immune cells. Based on these predictions, we suggested specific experimental studies that might allow for the validation or rejection of the proposed immune-evasion mechanism. PMID:29619027

Memorable Messages as Guides to Self-Assessment of Behavior: The Role of Instrumental Values.

ERIC Educational Resources Information Center

Smith, Sandi W.; Ellis, Jennifer Butler; Yoo, Hyo-Jin

2001-01-01

Uses control theory to predict how important instrumental values and internalized memorable messages work together when undergraduate students self-assess their previous behavior. Finds none of the four higher-order value factors predicted the hypothesized relationships among values, messages, and behaviors; but the value of…

Spontaneous Facial Mimicry in Response to Dynamic Facial Expressions

ERIC Educational Resources Information Center

Sato, Wataru; Yoshikawa, Sakiko

2007-01-01

Based on previous neuroscientific evidence indicating activation of the mirror neuron system in response to dynamic facial actions, we hypothesized that facial mimicry would occur while subjects viewed dynamic facial expressions. To test this hypothesis, dynamic/static facial expressions of anger/happiness were presented using computer-morphing…

University Students' Subjective Knowledge of Green Computing and Pro-Environmental Behavior

ERIC Educational Resources Information Center

Ahmad, Tunku Badariah Tunku; Nordin, Mohamad Sahari

2014-01-01

This cross-sectional survey examined the structure of university students' subjective knowledge of green computing--hypothesized to be a multidimensional construct with three important dimensions--and its association with pro-environmental behavior (PEB). Using a previously validated green computing questionnaire, data were collected from 842…

Alienation and the Ontology of Social Structure.

ERIC Educational Resources Information Center

Segalman, Ralph

Theoretical models of social structure are analyzed in light of modern work patterns, social affiliations, and social attitudes. It is hypothesized that previous paradigms for society were based on classic theory which analyzed the then emergent forms of social structure and relationships. Because social structures and relationships have changed,…

The Novice-Expert Continuum in Astronomy Knowledge

ERIC Educational Resources Information Center

Bryce, T. G. K.; Blown, E. J.

2012-01-01

The nature of expertise in astronomy was investigated across a broad spectrum of ages and experience in China and New Zealand. Five hypotheses (capable of quantification and statistical analysis) were used to probe types of expertise identified by previous researchers: (a) domain-specific knowledge-skill in the use of scientific vocabulary and…

Pharmacological Enhancement of mGluR5 Facilitates Contextual Fear Memory Extinction

ERIC Educational Resources Information Center

Sethna, Ferzin; Wang, Hongbing

2014-01-01

Behavioral exposure therapy, which involves extinction of the previously acquired fear, has been used to treat anxiety-related symptoms such as post-traumatic stress disorder. It has been hypothesized that proextinction pharmacotherapeutics may enhance the efficacy of exposure therapy. Systemic administration of the metabotropic glutamate receptor…

Quantifying the Qualitative: Measuring the Insight Experience

ERIC Educational Resources Information Center

Jarman, Matthew S.

2014-01-01

No scales currently exist that measure variability in the insight experience. Two scales were created to measure two factors hypothesized to be key drivers of the insight experience: insight radicality (i.e., perceived deviation between previous and new problem representations) and restructuring experience (i.e., the subjective experience of the…

Continuous nutrient administration decreases insulin sensitivity in neonatal pigs

USDA-ARS?s Scientific Manuscript database

We previously showed that chronic TPN compared to intermittent feeding of a formula results in hepatic insulin resistance and steatosis in neonatal pigs. We hypothesized that the route of feeding (IV vs enteral) rather than the nature of the diet (elemental vs polymeric) or the feeding regimen (cont...

Continuous administration of an elemental diet induces insulin resistance in neonatal pigs

USDA-ARS?s Scientific Manuscript database

We previously showed that total parenteral nutrition (TPN) compared to intermittent enteral feeding of a milk-based formula induces insulin resistance and hepatic steatosis in neonatal pigs. We hypothesized that intravenous (IV) feeding rather than the nature of the diet (elemental vs polymeric) or ...

A Case of Hand Waving: Action Synchrony and Person Perception

ERIC Educational Resources Information Center

Macrae, C. Neil; Duffy, Oonagh K.; Miles, Lynden K.; Lawrence, Julie

2008-01-01

While previous research has demonstrated that people's movements can become coordinated during social interaction, little is known about the cognitive consequences of behavioral synchrony. Given intimate links between the systems that regulate perception and action, we hypothesized that the synchronization of movements during a dyadic interaction…

Multilevel Confirmatory Factor Analysis of the Teacher My Class Inventory-Short Form

ERIC Educational Resources Information Center

Villares, Elizabeth; Mariani, Melissa; Sink, Christopher A.; Colvin, Kimberly

2016-01-01

Researchers analyzed data from elementary teachers (N = 233) to further establish the psychometric soundness of the Teacher My Class Inventory-Short Form. Supporting previous psychometric research, confirmatory factor analyses findings supported the factorial validity of the hypothesized five-factor solution. Internal reliability estimates were…

Visual Object Pattern Separation Varies in Older Adults

ERIC Educational Resources Information Center

Holden, Heather M.; Toner, Chelsea; Pirogovsky, Eva; Kirwan, C. Brock; Gilbert, Paul E.

2013-01-01

Young and nondemented older adults completed a visual object continuous recognition memory task in which some stimuli (lures) were similar but not identical to previously presented objects. The lures were hypothesized to result in increased interference and increased pattern separation demand. To examine variability in object pattern separation…

Reactivation-Dependent Amnesia in Pavlovian Approach and Instrumental Transfer

ERIC Educational Resources Information Center

Lee, Jonathan L. C.; Everitt, Barry J.

2008-01-01

The theory of memory reconsolidation relates to the hypothesized restabilisation process that occurs following the reactivation of a memory through retrieval. Thus, the demonstration of reactivation-dependent amnesia for a previously acquired memory is a prerequisite for showing that such a memory undergoes reconsolidation. Here, we show that the…

Client experiences of motivational interviewing: An interpersonal process recall study.

PubMed

Jones, Sarah A; Latchford, Gary; Tober, Gillian

2016-03-01

To explore clients' experience of the therapy process in motivational interviewing (MI) for alcohol abuse. A qualitative study using grounded theory. Interviews with nine clients were conducted using interpersonal process recall (IPR), a methodology which utilizes a video recording as a cue to aid memory recall. Clients watched a videotape of their MI session and were asked to identify and describe the important moments in the therapy session. The transcribed interviews were then analysed using grounded theory. A single session of MI is seen by the clients in this study as a complex interpersonal interaction between client and therapist, which impacts on the client's cognitive and affective intrapersonal processes. The themes which emerged partly confirm processes of MI previously hypothesized to be important, but also highlight the importance of factors common to all therapeutic approaches. The aspects of therapy which clients in this study felt were important are similar to those hypothesized to underlie the effectiveness of MI, including a non-confrontational approach, affirmation, and developing discrepancies between beliefs and behaviour. These were embedded in aspects common to all therapies, including the qualities of the therapist and the therapeutic relationship. Client's perspectives on therapeutic processes are an important area of research, and IPR is a particularly suitable method. © 2015 The British Psychological Society.

Determinants of the variations in self-reported health status among recent and more established immigrants in Canada.

PubMed

Subedi, Rajendra Prasad; Rosenberg, Mark Warren

2014-08-01

Studies have shown that immigrants are normally in better health on arrival compared to their Canadian-born counterparts. However, the health conditions of new immigrants deteriorate after a few years of their arrival in Canada. This phenomenon is popularly termed the "healthy immigrant effect" (HIE) in the immigrant health literature. Although different hypotheses have been proposed to understand HIE, the causes are subject to ongoing discussion. Unlike previous studies, this study explored the possible causes behind the variations in the health status of recent and more established immigrants comparing 2001 and 2010 Canadian Community Health Surveys (CCHS). Four different hypotheses - namely lifestyle change, barriers to health care services, poor social determinants of health, and work related stress - were tested to understand variations in health status. The study concludes that there is a statistically significant difference in the socioeconomic characteristics and health outcomes of immigrants having less than and more than 10 years of residency in Canada. Logistic regression models show that the health conditions of immigrants are associated with age, sex, ethnic origin, smoking habit, Body Mass Index (BMI), total household income, number of consultations made with a family doctor per year and work related stress. Copyright © 2014 Elsevier Ltd. All rights reserved.

Testing Adaptive Hypotheses of Convergence with Functional Landscapes: A Case Study of Bone-Cracking Hypercarnivores

PubMed Central

Tseng, Zhijie Jack

2013-01-01

Morphological convergence is a well documented phenomenon in mammals, and adaptive explanations are commonly employed to infer similar functions for convergent characteristics. I present a study that adopts aspects of theoretical morphology and engineering optimization to test hypotheses about adaptive convergent evolution. Bone-cracking ecomorphologies in Carnivora were used as a case study. Previous research has shown that skull deepening and widening are major evolutionary patterns in convergent bone-cracking canids and hyaenids. A simple two-dimensional design space, with skull width-to-length and depth-to-length ratios as variables, was used to examine optimized shapes for two functional properties: mechanical advantage (MA) and strain energy (SE). Functionality of theoretical skull shapes was studied using finite element analysis (FEA) and visualized as functional landscapes. The distribution of actual skull shapes in the landscape showed a convergent trend of plesiomorphically low-MA and moderate-SE skulls evolving towards higher-MA and moderate-SE skulls; this is corroborated by FEA of 13 actual specimens. Nevertheless, regions exist in the landscape where high-MA and lower-SE shapes are not represented by existing species; their vacancy is observed even at higher taxonomic levels. Results highlight the interaction of biomechanical and non-biomechanical factors in constraining general skull dimensions to localized functional optima through evolution. PMID:23734244

Investigating the Global Dispersal of Chickens in Prehistory Using Ancient Mitochondrial DNA Signatures

PubMed Central

Storey, Alice A.; Athens, J. Stephen; Bryant, David; Carson, Mike; Emery, Kitty; deFrance, Susan; Higham, Charles; Huynen, Leon; Intoh, Michiko; Jones, Sharyn; Kirch, Patrick V.; Ladefoged, Thegn; McCoy, Patrick; Morales-Muñiz, Arturo; Quiroz, Daniel; Reitz, Elizabeth; Robins, Judith; Walter, Richard; Matisoo-Smith, Elizabeth

2012-01-01

Data from morphology, linguistics, history, and archaeology have all been used to trace the dispersal of chickens from Asian domestication centers to their current global distribution. Each provides a unique perspective which can aid in the reconstruction of prehistory. This study expands on previous investigations by adding a temporal component from ancient DNA and, in some cases, direct dating of bones of individual chickens from a variety of sites in Europe, the Pacific, and the Americas. The results from the ancient DNA analyses of forty-eight archaeologically derived chicken bones provide support for archaeological hypotheses about the prehistoric human transport of chickens. Haplogroup E mtDNA signatures have been amplified from directly dated samples originating in Europe at 1000 B.P. and in the Pacific at 3000 B.P. indicating multiple prehistoric dispersals from a single Asian centre. These two dispersal pathways converged in the Americas where chickens were introduced both by Polynesians and later by Europeans. The results of this study also highlight the inappropriate application of the small stretch of D-loop, traditionally amplified for use in phylogenetic studies, to understanding discrete episodes of chicken translocation in the past. The results of this study lead to the proposal of four hypotheses which will require further scrutiny and rigorous future testing. PMID:22848352

Investigating the global dispersal of chickens in prehistory using ancient mitochondrial DNA signatures.

PubMed

Storey, Alice A; Athens, J Stephen; Bryant, David; Carson, Mike; Emery, Kitty; deFrance, Susan; Higham, Charles; Huynen, Leon; Intoh, Michiko; Jones, Sharyn; Kirch, Patrick V; Ladefoged, Thegn; McCoy, Patrick; Morales-Muñiz, Arturo; Quiroz, Daniel; Reitz, Elizabeth; Robins, Judith; Walter, Richard; Matisoo-Smith, Elizabeth

2012-01-01

Data from morphology, linguistics, history, and archaeology have all been used to trace the dispersal of chickens from Asian domestication centers to their current global distribution. Each provides a unique perspective which can aid in the reconstruction of prehistory. This study expands on previous investigations by adding a temporal component from ancient DNA and, in some cases, direct dating of bones of individual chickens from a variety of sites in Europe, the Pacific, and the Americas. The results from the ancient DNA analyses of forty-eight archaeologically derived chicken bones provide support for archaeological hypotheses about the prehistoric human transport of chickens. Haplogroup E mtDNA signatures have been amplified from directly dated samples originating in Europe at 1000 B.P. and in the Pacific at 3000 B.P. indicating multiple prehistoric dispersals from a single Asian centre. These two dispersal pathways converged in the Americas where chickens were introduced both by Polynesians and later by Europeans. The results of this study also highlight the inappropriate application of the small stretch of D-loop, traditionally amplified for use in phylogenetic studies, to understanding discrete episodes of chicken translocation in the past. The results of this study lead to the proposal of four hypotheses which will require further scrutiny and rigorous future testing.

Social and economic ideologies differentially predict prejudice across the political spectrum, but social issues are most divisive.

PubMed

Crawford, Jarret T; Brandt, Mark J; Inbar, Yoel; Chambers, John R; Motyl, Matt

2017-03-01

Liberals and conservatives both express prejudice toward ideologically dissimilar others (Brandt et al., 2014). Previous work on ideological prejudice did not take advantage of evidence showing that ideology is multidimensional, with social and economic ideologies representing related but separable belief systems. In 5 studies (total N = 4912), we test 3 competing hypotheses of a multidimensional account of ideological prejudice. The dimension-specific symmetry hypothesis predicts that social and economic ideologies differentially predict prejudice against targets who are perceived to vary on the social and economic political dimensions, respectively. The social primacy hypothesis predicts that such ideological worldview conflict is experienced more strongly along the social than economic dimension. The social-specific asymmetry hypothesis predicts that social conservatives will be more prejudiced than social liberals, with no specific hypotheses for the economic dimension. Using multiple target groups, multiple prejudice measures (e.g., global evaluations, behavior), and multiple social and economic ideology measures (self-placement, issue positions), we found relatively consistent support for the dimension-specific symmetry and social primacy hypotheses, and no support for the social-specific asymmetry hypothesis. These results suggest that worldview conflict and negative intergroup attitudes and behaviors are dimension-specific, but that the social dimension appears to inspire more political conflict than the economic dimension. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Hypothesizing dopaminergic genetic antecedents in schizophrenia and substance seeking behavior.

PubMed

Blum, Kenneth; Oscar-Berman, Marlene; Badgaiyan, Rajendra D; Palomo, Tomas; Gold, Mark S

2014-05-01

The dopamine system has been implicated in both substance use disorder (SUD) and schizophrenia. A recent meta-analysis suggests that A1 allele of the DRD2 gene imposes genetic risk for SUD, especially alcoholism and has been implicated in Reward Deficiency Syndrome (RDS). We hypothesize that dopamine D2 receptor (DRD2) gene Taq1 A2 allele is associated with a subtype of non-SUD schizophrenics and as such may act as a putative protective agent against the development of addiction to alcohol or other drugs of abuse. Schizophrenics with SUD may be carriers of the DRD2 Taq1 A1 allele, and/or other RDS reward polymorphisms and have hypodopaminergic reward function. One plausible mechanism for alcohol seeking in schizophrenics with SUD, based on previous research, may be a deficiency of gamma type endorphins that has been linked to schizophrenic type psychosis. We also propose that alcohol seeking behavior in schizophrenics, may serve as a physiological self-healing process linked to the increased function of the gamma endorphins, thereby reducing abnormal dopaminergic activity at the nucleus accumbens (NAc). These hypotheses warrant further investigation and cautious interpretation. We, therefore, encourage research involving neuroimaging, genome wide association studies (GWAS), and epigenetic investigation into the relationship between neurogenetics and systems biology to unravel the role of dopamine in psychiatric illness and SUD. Copyright © 2014 Elsevier Ltd. All rights reserved.

Hypothesizing Dopaminergic Genetic Antecedents in Schizophrenia and Substance Seeking Behavior

PubMed Central

Blum, Kenneth; Oscar-Berman, Marlene; Badgaiyan, Rajendra; Palomo, Tomas; Gold, Mark S.

2014-01-01

The dopamine system has been implicated in both substance use disorder (SUD) and schizophrenia. A recent meta- analysis suggests that A1 allele of the DRD2 gene imposes genetic risk for SUD, especially alcoholism and has been implicated in Reward Deficiency Syndrome (RDS). We hypothesize that dopamine D2 receptor (DRD2) gene Taq1 A2 allele is associated with a subtype of non- SUD schizophrenics and as such may act as a putative protective agent against the development of addiction to alcohol or other drugs of abuse. Schizophrenics with SUD may be carriers of the DRD2 Taq1 A1 allele, and/or other RDS reward polymorphisms and have hypodopaminergic reward function. One plausible mechanism for alcohol seeking in schizophrenics with SUD, based on previous research, may be a deficiency of gamma type endorphins that has been linked to schizophrenic type psychosis.. We also propose that alcohol seeking behavior in schizophrenics, may serve as a physiological self-healing process linked to the increased function of the gamma endorphins, thereby reducing abnormal dopaminergic activity at the nucleus accumbens (NAc). These hypotheses warrant further investigation and cautious interpretation. We, therefore, encourage research involving neuroimaging, genome wide association studies (GWAS), and epigenetic investigation into the relationship between neurogenetics and systems biology to unravel the role of dopamine in psychiatric illness and SUD. PMID:24636783

Investigating the relationship between the practice of pharmaceutical care, construed external image, organizational identification, and job turnover intention of community pharmacists.

PubMed

O'Neill, Jessica L; Gaither, Caroline A

2007-12-01

Pharmacy employers are being challenged to recruit and retain qualified employees. Our study hypothesized that pharmacists who practice pharmaceutical care have an attractive construed external image (how employees think outsiders view their organization), which strengthens their organizational identification (perceptions of oneness with or belongingness to the organization) and decreases job turnover intention (thoughts of quitting/searching for another job). A 7-page questionnaire was mailed to the homes of a random sample of 759 licensed pharmacists practicing in the United States. Participants had the option of returning the completed survey via postal mail or a Web site. The study variables were measured with previously validated scales. Structural equation modeling with latent variables evaluated the hypothesized relationships. Several demographic variables were included. Responses were received from 252 subjects (33%); 121 were community pharmacists. As hypothesized, organizational identification and job turnover intention were significantly related (B=-0.24) as well as construed external image and organizational identification (B=0.41). The practice of pharmaceutical care and construed external image were not significantly correlated (B=0.10). Although not hypothesized, construed external image was directly related to job turnover intention (B=-0.25). The effects of the practice of pharmaceutical care on job turnover intention were mediated through organizational identification. Position had significant effects. One additional benefit to the practice of pharmaceutical care may be strengthened organizational identification. Pharmacists' perception of the image of their employer may increase organizational identification and decrease job turnover intention. An understanding of the organizational identification of pharmacists would be useful in decreasing job turnover intention. Given the current demand for pharmacists, this is a worthwhile endeavor. Future research should focus on other predictors of construed external image and ways to enhance organizational identification. Encouraging the practice of pharmaceutical care may be 1 such way.

Functional morphology of the bovid astragalus in relation to habitat: controlling phylogenetic signal in ecomorphology.

PubMed

Barr, W Andrew

2014-11-01

Bovid astragali are one of the most commonly preserved bones in the fossil record. Accordingly, astragali are an important target for studies seeking to predict the habitat preferences of fossil bovids based on bony anatomy. However, previous work has not tested functional hypotheses linking astragalar morphology with habitat while controlling for body size and phylogenetic signal. This article presents a functional framework relating the morphology of the bovid astragalus to habitat-specific locomotor ecology and tests four hypotheses emanating from this framework. Highly cursorial bovids living in structurally open habitats are hypothesized to differ from their less cursorial closed-habitat dwelling relatives in having (1) relatively short astragali to maintain rotational speed throughout the camming motion of the rotating astragalus, (2) a greater range of angular excursion at the hock, (3) relatively larger joint surface areas, and (4) a more pronounced "spline-and-groove" morphology promoting lateral joint stability. A diverse sample of 181 astragali from 50 extant species was scanned using a Next Engine laser scanner. Species were assigned to one of four habitat categories based on the published ecological literature. A series of 11 linear measurements and three joint surface areas were measured on each astragalus. A geometric mean body size proxy was used to size-correct the measurement data. Phylogenetic generalized least squares (PGLS) was used to test for differences between habitat categories while controlling for body size differences and phylogenetic signal. Statistically significant PGLS results support Hypotheses 1 and 2 (which are not mutually exclusive) as well as Hypothesis 3. No support was found for Hypothesis 4. These findings confirm that the morphology of the bovid astragalus is related to habitat-specific locomotor ecology, and that this relationship is statistically significant after controlling for body size and phylogeny. Thus, this study validates the use of this bone as an ecomorphological indicator. © 2014 Wiley Periodicals, Inc.

Do Drinking Episodes Contribute to Sexual Aggression Perpetration in College Men?

PubMed

Testa, Maria; Parks, Kathleen A; Hoffman, Joseph H; Crane, Cory A; Leonard, Kenneth E; Shyhalla, Kathleen

2015-07-01

Survey and experimental analog studies suggest that alcohol consumption contributes to perpetration of sexual aggression. However, few studies have considered the temporal association between naturally occurring episodes of drinking and subsequent sexual aggression. This daily report study was designed to examine whether alcohol consumption increases the odds of aggressive sexual activity within the next 4 hours. First-year male college students (N = 427) completed daily online reports of drinking and sexual activity for up to 56 days. Multilevel modeling was used to determine whether drinking episodes increased the odds of the following outcomes occurring within 4 hours: (a) aggressive sex with a new partner, (b) non-aggressive sex with a new partner, (c) aggressive sex with a previous partner, and (d) non-aggressive sex with a previous partner. Drinking episodes increased the odds of both aggressive and non-aggressive sex with a new partner. In contrast, drinking episodes did not predict aggression involving previous partners and decreased the odds of non-aggressive sex with a previous partner. Contrary to hypotheses, individual difference variables associated with propensity toward sexual aggression (sexual misperception, antisocial behavior, hostility toward women) did not interact with daily alcohol. The complex pattern of results is more consistent with situational as opposed to pharmacological effects of alcohol on sexual aggression and suggests that prevention efforts focus on drinking contexts known to facilitate sexual activity.

Do Drinking Episodes Contribute to Sexual Aggression Perpetration in College Men?

PubMed Central

Testa, Maria; Parks, Kathleen A.; Hoffman, Joseph H.; Crane, Cory A.; Leonard, Kenneth E.; Shyhalla, Kathleen

2015-01-01

Objective: Survey and experimental analog studies suggest that alcohol consumption contributes to perpetration of sexual aggression. However, few studies have considered the temporal association between naturally occurring episodes of drinking and subsequent sexual aggression. This daily report study was designed to examine whether alcohol consumption increases the odds of aggressive sexual activity within the next 4 hours. Method: First-year male college students (N = 427) completed daily online reports of drinking and sexual activity for up to 56 days. Multilevel modeling was used to determine whether drinking episodes increased the odds of the following outcomes occurring within 4 hours: (a) aggressive sex with a new partner, (b) non-aggressive sex with a new partner, (c) aggressive sex with a previous partner, and (d) non-aggressive sex with a previous partner. Results: Drinking episodes increased the odds of both aggressive and non-aggressive sex with a new partner. In contrast, drinking episodes did not predict aggression involving previous partners and decreased the odds of non-aggressive sex with a previous partner. Contrary to hypotheses, individual difference variables associated with propensity toward sexual aggression (sexual misperception, antisocial behavior, hostility toward women) did not interact with daily alcohol. Conclusions: The complex pattern of results is more consistent with situational as opposed to pharmacological effects of alcohol on sexual aggression and suggests that prevention efforts focus on drinking contexts known to facilitate sexual activity. PMID:26098025

Diel metabolomics analysis of a hot spring chlorophototrophic microbial mat leads to new hypotheses of community member metabolisms

DOE PAGES

Kim, Young-Mo; Nowack, Shane; Olsen, Millie; ...

2015-04-17

Dynamic environmental factors such as light, nutrients, salt, and temperature continuously affect chlorophototrophic microbial mats, requiring adaptative and acclimative responses to stabilize composition and function. Quantitative metabolomics analysis can provide insights into metabolite dynamics for understanding community response to such changing environmental conditions. In this study, we quantified volatile organic acids, polar metabolites (amino acids, glycolytic and citric acid cycle intermediates, nucleobases, nucleosides, and sugars), wax esters, and polyhydroxyalkanoates, resulting in the identification of 104 metabolites and related molecules in thermal chlorophototrophic microbial mat cores collected over a diel cycle in Mushroom Spring, Yellowstone National Park. A limited number ofmore » predominant taxa inhabiting this community and their functional potentials have been previously identified through metagenomic and metatranscriptomic analyses and in situ metabolisms and metabolic interactions among these taxa have been hypothesized. Our metabolomics results confirmed the diel cycling of photorespiration (e.g. glycolate) and fermentation (e.g. acetate, propionate, and lactate) products, the carbon storage polymers polyhydroxyalkanoates, and dissolved gases (e.g. H2 and CO2) in the waters overlying the mat, which were hypothesized to occur in major mat chlorophototrophic community members. In addition, we have formulated the following new hypotheses: 1) the morning hours are a time of biosynthesis of amino acids, DNA, and RNA; 2) Synechococcus spp. produce CH4 via metabolism of phosphonates, and photo-inhibited cells may also produce lactate via fermentation as an alternate metabolism; 3) glycolate and lactate are exchanged among Synechococcus and Roseiflexus spp.; and 4) fluctuations in many metabolite pools (e.g. wax esters) at different times of day result from species found at different depths within the mat responding to temporal differences in their niches.« less

Diel metabolomics analysis of a hot spring chlorophototrophic microbial mat leads to new hypotheses of community member metabolisms

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

Kim, Young-Mo; Nowack, Shane; Olsen, Millie

Dynamic environmental factors such as light, nutrients, salt, and temperature continuously affect chlorophototrophic microbial mats, requiring adaptative and acclimative responses to stabilize composition and function. Quantitative metabolomics analysis can provide insights into metabolite dynamics for understanding community response to such changing environmental conditions. In this study, we quantified volatile organic acids, polar metabolites (amino acids, glycolytic and citric acid cycle intermediates, nucleobases, nucleosides, and sugars), wax esters, and polyhydroxyalkanoates, resulting in the identification of 104 metabolites and related molecules in thermal chlorophototrophic microbial mat cores collected over a diel cycle in Mushroom Spring, Yellowstone National Park. A limited number ofmore » predominant taxa inhabiting this community and their functional potentials have been previously identified through metagenomic and metatranscriptomic analyses and in situ metabolisms and metabolic interactions among these taxa have been hypothesized. Our metabolomics results confirmed the diel cycling of photorespiration (e.g. glycolate) and fermentation (e.g. acetate, propionate, and lactate) products, the carbon storage polymers polyhydroxyalkanoates, and dissolved gases (e.g. H2 and CO2) in the waters overlying the mat, which were hypothesized to occur in major mat chlorophototrophic community members. In addition, we have formulated the following new hypotheses: 1) the morning hours are a time of biosynthesis of amino acids, DNA, and RNA; 2) Synechococcus spp. produce CH4 via metabolism of phosphonates, and photo-inhibited cells may also produce lactate via fermentation as an alternate metabolism; 3) glycolate and lactate are exchanged among Synechococcus and Roseiflexus spp.; and 4) fluctuations in many metabolite pools (e.g. wax esters) at different times of day result from species found at different depths within the mat responding to temporal differences in their niches.« less

Estimation from PET data of transient changes in dopamine concentration induced by alcohol: support for a non-parametric signal estimation method

NASA Astrophysics Data System (ADS)

Constantinescu, C. C.; Yoder, K. K.; Kareken, D. A.; Bouman, C. A.; O'Connor, S. J.; Normandin, M. D.; Morris, E. D.

2008-03-01

We previously developed a model-independent technique (non-parametric ntPET) for extracting the transient changes in neurotransmitter concentration from paired (rest & activation) PET studies with a receptor ligand. To provide support for our method, we introduced three hypotheses of validation based on work by Endres and Carson (1998 J. Cereb. Blood Flow Metab. 18 1196-210) and Yoder et al (2004 J. Nucl. Med. 45 903-11), and tested them on experimental data. All three hypotheses describe relationships between the estimated free (synaptic) dopamine curves (FDA(t)) and the change in binding potential (ΔBP). The veracity of the FDA(t) curves recovered by nonparametric ntPET is supported when the data adhere to the following hypothesized behaviors: (1) ΔBP should decline with increasing DA peak time, (2) ΔBP should increase as the strength of the temporal correlation between FDA(t) and the free raclopride (FRAC(t)) curve increases, (3) ΔBP should decline linearly with the effective weighted availability of the receptor sites. We analyzed regional brain data from 8 healthy subjects who received two [11C]raclopride scans: one at rest, and one during which unanticipated IV alcohol was administered to stimulate dopamine release. For several striatal regions, nonparametric ntPET was applied to recover FDA(t), and binding potential values were determined. Kendall rank-correlation analysis confirmed that the FDA(t) data followed the expected trends for all three validation hypotheses. Our findings lend credence to our model-independent estimates of FDA(t). Application of nonparametric ntPET may yield important insights into how alterations in timing of dopaminergic neurotransmission are involved in the pathologies of addiction and other psychiatric disorders.

Diel metabolomics analysis of a hot spring chlorophototrophic microbial mat leads to new hypotheses of community member metabolisms

PubMed Central

Kim, Young-Mo; Nowack, Shane; Olsen, Millie T.; Becraft, Eric D.; Wood, Jason M.; Thiel, Vera; Klapper, Isaac; Kühl, Michael; Fredrickson, James K.; Bryant, Donald A.; Ward, David M.; Metz, Thomas O.

2015-01-01

Dynamic environmental factors such as light, nutrients, salt, and temperature continuously affect chlorophototrophic microbial mats, requiring adaptive and acclimative responses to stabilize composition and function. Quantitative metabolomics analysis can provide insights into metabolite dynamics for understanding community response to such changing environmental conditions. In this study, we quantified volatile organic acids, polar metabolites (amino acids, glycolytic and citric acid cycle intermediates, nucleobases, nucleosides, and sugars), wax esters, and polyhydroxyalkanoates, resulting in the identification of 104 metabolites and related molecules in thermal chlorophototrophic microbial mat cores collected over a diel cycle in Mushroom Spring, Yellowstone National Park. A limited number of predominant taxa inhabit this community and their functional potentials have been previously identified through metagenomic and metatranscriptomic analyses and in situ metabolisms, and metabolic interactions among these taxa have been hypothesized. Our metabolomics results confirmed the diel cycling of photorespiration (e.g., glycolate) and fermentation (e.g., acetate, propionate, and lactate) products, the carbon storage polymers polyhydroxyalkanoates, and dissolved gasses (e.g., H2 and CO2) in the waters overlying the mat, which were hypothesized to occur in major mat chlorophototrophic community members. In addition, we have formulated the following new hypotheses: (1) the morning hours are a time of biosynthesis of amino acids, DNA, and RNA; (2) photo-inhibited cells may also produce lactate via fermentation as an alternate metabolism; (3) glycolate and lactate are exchanged among Synechococcus and Roseiflexus spp.; and (4) fluctuations in many metabolite pools (e.g., wax esters) at different times of day result from species found at different depths within the mat responding to temporal differences in their niches. PMID:25941514

Sources of science self-efficacy beliefs of middle school students

NASA Astrophysics Data System (ADS)

Britner, Shari L.; Pajares, Frank

2006-05-01

The purpose of this study was to investigate the degree to which A. Bandura's ([1997]) hypothesized sources of self-efficacy predict the science self-efficacy beliefs of middle school students (N = 319), to replicate previous findings that science self-efficacy predicts science achievement, and to explore how science self-efficacy and its antecedents differ by gender. Significant correlations were found between mastery experiences, vicarious experiences, social persuasions, physiological arousal, and self-efficacy. Only mastery experiences significantly predicted science self-efficacy. Girls reported stronger science self-efficacy than did boys. Findings support and extend the theoretical tenets of Bandura's social cognitive theory.

Expression of anger as a function of assertiveness and sex.

PubMed

Doyle, M A; Biaggio, M K

1981-01-01

Examined differences between asserters and nonasserters and between the sexes on anger expression. Thirty-seven male and 53 female college students were administered the College Self-Expression Scale, the Buss Durkee Hostility Inventory, and the Anger Self-Report. As hypothesized, asserters and males expressed more anger and aggression, and nonasserters experienced more covert anger. The clinical/treatment implications of these findings were discussed. A finding discrepant with previous research and the present researchers' expectations, that men scored higher than women on guilt and condemnation of anger, was thought to reflect this study's sample rather than an actual population difference.

A novel statistical approach shows evidence for multi-system physiological dysregulation during aging.

PubMed

Cohen, Alan A; Milot, Emmanuel; Yong, Jian; Seplaki, Christopher L; Fülöp, Tamàs; Bandeen-Roche, Karen; Fried, Linda P

2013-03-01

Previous studies have identified many biomarkers that are associated with aging and related outcomes, but the relevance of these markers for underlying processes and their relationship to hypothesized systemic dysregulation is not clear. We address this gap by presenting a novel method for measuring dysregulation via the joint distribution of multiple biomarkers and assessing associations of dysregulation with age and mortality. Using longitudinal data from the Women's Health and Aging Study, we selected a 14-marker subset from 63 blood measures: those that diverged from the baseline population mean with age. For the 14 markers and all combinatorial sub-subsets we calculated a multivariate distance called the Mahalanobis distance (MHBD) for all observations, indicating how "strange" each individual's biomarker profile was relative to the baseline population mean. In most models, MHBD correlated positively with age, MHBD increased within individuals over time, and higher MHBD predicted higher risk of subsequent mortality. Predictive power increased as more variables were incorporated into the calculation of MHBD. Biomarkers from multiple systems were implicated. These results support hypotheses of simultaneous dysregulation in multiple systems and confirm the need for longitudinal, multivariate approaches to understanding biomarkers in aging. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Unsupervised text mining for assessing and augmenting GWAS results.

PubMed

Ailem, Melissa; Role, François; Nadif, Mohamed; Demenais, Florence

2016-04-01

Text mining can assist in the analysis and interpretation of large-scale biomedical data, helping biologists to quickly and cheaply gain confirmation of hypothesized relationships between biological entities. We set this question in the context of genome-wide association studies (GWAS), an actively emerging field that contributed to identify many genes associated with multifactorial diseases. These studies allow to identify groups of genes associated with the same phenotype, but provide no information about the relationships between these genes. Therefore, our objective is to leverage unsupervised text mining techniques using text-based cosine similarity comparisons and clustering applied to candidate and random gene vectors, in order to augment the GWAS results. We propose a generic framework which we used to characterize the relationships between 10 genes reported associated with asthma by a previous GWAS. The results of this experiment showed that the similarities between these 10 genes were significantly stronger than would be expected by chance (one-sided p-value<0.01). The clustering of observed and randomly selected gene also allowed to generate hypotheses about potential functional relationships between these genes and thus contributed to the discovery of new candidate genes for asthma. Copyright © 2016 Elsevier Inc. All rights reserved.

Functional modularity in lake-dwelling characin fishes of Mexico

PubMed Central

Bautista, Amando; Herder, Fabian; Doadrio, Ignacio

2017-01-01

Modular evolution promotes evolutionary change, allowing independent variation across morphological units. Recent studies have shown that under contrasting ecological pressures, patterns of modularity could be related to divergent evolution. The main goal of the present study was to evaluate the presence of modular evolution in two sister lacustrine species, Astyanax aeneus and A. caballeroi, which are differentiated by their trophic habits. Two different datasets were analyzed: (1) skull X-rays from 73 specimens (35 A. aeneus and 38 A. caballeroi) to characterize skull variation patterns, considering both species and sex effects. For this dataset, three different modularity hypotheses were tested, previously supported in other lacustrine divergent species; (2) a complete body shape dataset was also tested for four modularity hypotheses, which included a total of 196 individuals (110 Astyanax aeneus and 86 A. caballeroi). Skull shape showed significant differences among species and sex (P < 0.001), where Astyanax caballeroi species showed an upwardly projected mandible and larger preorbital region. For the skull dataset, the modularity hypothesis ranked first included three partitioning modules. While for the complete body dataset the best ranked hypothesis included two modules (head vs the rest of the body), being significant only for A. caballeroi. PMID:28951817

Functional modularity in lake-dwelling characin fishes of Mexico.

PubMed

Ornelas-García, Claudia Patricia; Bautista, Amando; Herder, Fabian; Doadrio, Ignacio

2017-01-01

Modular evolution promotes evolutionary change, allowing independent variation across morphological units. Recent studies have shown that under contrasting ecological pressures, patterns of modularity could be related to divergent evolution. The main goal of the present study was to evaluate the presence of modular evolution in two sister lacustrine species, Astyanax aeneus and A. caballeroi , which are differentiated by their trophic habits. Two different datasets were analyzed: (1) skull X-rays from 73 specimens (35 A. aeneus and 38 A. caballeroi ) to characterize skull variation patterns, considering both species and sex effects. For this dataset, three different modularity hypotheses were tested, previously supported in other lacustrine divergent species; (2) a complete body shape dataset was also tested for four modularity hypotheses, which included a total of 196 individuals (110 Astyanax aeneus and 86 A. caballeroi ). Skull shape showed significant differences among species and sex ( P  < 0.001), where Astyanax caballeroi species showed an upwardly projected mandible and larger preorbital region. For the skull dataset, the modularity hypothesis ranked first included three partitioning modules. While for the complete body dataset the best ranked hypothesis included two modules (head vs the rest of the body), being significant only for A. caballeroi .

Factors affecting construction performance: exploratory factor analysis

NASA Astrophysics Data System (ADS)

Soewin, E.; Chinda, T.

2018-04-01

The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

FORUM: Dynamics and Causation of Environmental Equity, Locally Unwanted Land Uses, and Neighborhood Changes

PubMed

Liu

1997-09-01

/ Why are some environmental risks distributed disproportionately in the neighborhoods of the minorities and the poor? A hypothesis was proposed in a recent study that market dynamics contributed to the current environmental inequity. That is, locally unwanted land uses (LULUs) make the host communities home to more poor people and people of color. This hypothesis was allegedly supported by a Houston case study, whereby its author analyzed the postsiting changes of the socioeconomic characteristics of the neighborhoods surrounding solid waste facilities. I argue that such an analysis of postsiting changes alone is insufficient to test the causation hypothesis. Instead, I propose a conceptual framework for analysis of environmental equity dynamics and causation. I suggest that the presiting neighborhood dynamics and the characteristics of control neighborhoods be analyzed as the first test for the causation hypothesis. Furthermore, I present theories of neighborhood change and then examine alternative hypotheses that these theories offer for explaining neighborhood changes and for the roles of LULUs in neighborhood changes. These alternative hypotheses should be examined when analyzing the relationship between LULUs and neighborhood changes in a metropolitan area. Using this framework of analysis, I revisited the Houston case. First, I found no evidence that provided support for the hypothesis that the presence of LULUs made the neighborhoods home to more blacks and poor people, contrary to the conclusion made by the previous study. Second, I examined alternative hypotheses for explaining neighborhood changes-invasion-succession, other push forces, and neighborhood life-cycle; the former two might offer better explanation.KEY WORDS: Environmental equity and justice; Locally unwanted lane uses; Siting; Market dynamics; Invasion-succession; Neighborhood changes

Heterogeneous activity causes a nonlinear increase in the group energy use of ant workers isolated from queen and brood.

PubMed

Ferral, Nolan; Holloway, Kyara; Li, Mingzhong; Yin, Zhaozheng; Hou, Chen

2018-06-01

Increasing evidence has shown that the energy use of ant colonies increases sublinearly with colony size so that large colonies consume less per capita energy than small colonies. It has been postulated that social environment (e.g., in the presence of queen and brood) is critical for the sublinear group energetics, and a few studies of ant workers isolated from queens and brood observed linear relationships between group energetics and size. In this paper, we hypothesize that the sublinear energetics arise from the heterogeneity of activity in ant groups, that is, large groups have relatively more inactive members than small groups. We further hypothesize that the energy use of ant worker groups that are allowed to move freely increases more slowly than the group size even if they are isolated from queen and brood. Previous studies only provided indirect evidence for these hypotheses due to technical difficulties. In this study, we applied the automated behavioral monitoring and respirometry simultaneously on isolated worker groups for long time periods, and analyzed the image with the state-of-the-art algorithms. Our results show that when activity was not confined, large groups had lower per capita energy use, a lower percentage of active members, and lower average walking speed than small groups; while locomotion was confined, however, the per capita energy use was a constant regardless of the group size. The quantitative analysis shows a direct link between variation in group energy use and the activity level of ant workers when isolated from queen and brood. © 2016 Institute of Zoology, Chinese Academy of Sciences.

The effects of ambivalent fertility desires on pregnancy risk in young women in Michigan, United States

PubMed Central

Miller, Warren B.; Barber, Jennifer S.; Gatny, Heather H.

2012-01-01

Many different definitions of the construct of motivational ambivalence have appeared in the literature on reproductive health. Using a theoretical framework in which motivational ambivalence is defined as an interaction between positive and negative pregnancy desires, we propose two hypotheses. The first is that positive and negative pregnancy desires independently predict the risk of an unplanned pregnancy. The second is that ambivalence and three related constructs that are also based on the interaction between positive and negative desires are each important predictors of pregnancy risk. We use weekly journal data collected from a U.S. sample of 1,003 women aged 18–19 years and conduct hazard model analysis to test our hypotheses. Using both dummy and continuous predictors, we report results that confirm both hypotheses. The proposed interaction framework has demonstrated validity, compares favorably with previously reported alternative approaches, and incorporates a set of constructs that have potential importance for further research directed at the prevention of unplanned pregnancy. PMID:23234316

On the evolution of reproductive restraint in malaria

PubMed Central

Mideo, Nicole; Day, Troy

2008-01-01

Malaria is one of the leading causes of death among infectious diseases in the world, claiming over one million lives every year. By these standards, this highly complex parasite is extremely successful at generating new infections. Somewhat surprisingly, however, many malaria species seem to invest relatively little in gametocytes, converting only a small percentage of circulating asexual parasite forms into this transmissible form. In this article, we use mathematical models to explore three of the hypotheses that have been proposed to explain this apparent ‘reproductive restraint’ and develop a novel, fourth hypothesis. We find that only one of the previous three hypotheses we explore can explain such low gametocyte conversion rates, and this hypothesis involves a very specific form of density-dependent transmission-blocking immunity. Our fourth hypothesis also provides a potential explanation and is based on the occurrence of multiple infections and the resultant within-host competition between malaria strains that this entails. Further experimental work is needed to determine which of these two hypotheses provides the most likely explanation. PMID:18303001

Testing two principles of the Health Action Process Approach in individuals with type 2 diabetes.

PubMed

Lippke, Sonia; Plotnikoff, Ronald C

2014-01-01

The Health Action Process Approach (HAPA) proposes principles that can be translated into testable hypotheses. This is one of the first studies to have explicitly tested HAPA's first 2 principles, which are (1) health behavior change process can be subdivided into motivation and volition, and (2) volition can be grouped into intentional and action stages. The 3 stage groups are labeled preintenders, intenders, and actors. The hypotheses of the HAPA model were investigated in a sample of 1,193 individuals with Type 2 diabetes. Study participants completed a questionnaire assessing the HAPA variables. The hypotheses were evaluated by examining mean differences of test variables and by the use of multigroup structural equation modeling (MSEM). Findings support the HAPA's 2 principles and 3 distinct stages. The 3 HAPA stages were significantly different in several stage-specific variables, and discontinuity patterns were found in terms of nonlinear trends across means. In terms of predicting goals, action planning, and behavior, differences transpired between the 2 motivational stages (preintenders and intenders), and between the 2 volitional stages (intenders and actors). Results indicate implications for supporting behavior change processes, depending on in which stage a person is at: All individuals should be helped to increase self-efficacy. Preintenders and intenders require interventions targeting outcome expectancies. Actors benefit from an improvement in action planning to maintain and increase their previous behavior. Overall, the first 2 principles of the HAPA were supported and some evidence for the other principles was found. Future research should experimentally test these conclusions. 2014 APA, all rights reserved

Phylogenetic relationships and biogeography of the genus Algansea Girard (Cypriniformes: Cyprinidae) of central Mexico inferred from molecular data

PubMed Central

Pérez-Rodríguez, Rodolfo; Domínguez-Domínguez, Omar; de León, Gerardo Pérez Ponce; Doadrio, Ignacio

2009-01-01

Background The genus Algansea is one of the most representative freshwater fish groups in central Mexico due to its wide geographic distribution and unusual level of endemicity. Despite the small number of species, this genus has had an unsettled taxonomic history due to high levels of intraspecific morphological variation. Moreover, several phylogenetic hypotheses among congeners have been proposed but have had the following shortcomings: the use of homoplasious morphological characters, the use of character codification and polarisation methods that lacked objectivity, and incomplete taxonomic sampling. In this study, a phylogenetic analysis among species of Algansea is presented. This analysis is based upon two molecular markers, the mitochondrial gene cytochrome b and the first intron of the ribosomal protein S7 gene. Results Bayesian analysis based on a combined matrix (cytochrome b and first intron S7) showed that Algansea is a monophyletic group and that Agosia chrysogaster is the sister group. Divergence times dated the origin of the genus around 16.6 MYA, with subsequent cladogenetic events occurring between 6.4 and 2.8 MYA. When mapped onto the molecular phylogenetic hypothesis, the character states of three morphological characters did not support previous hypotheses on the evolution of morphological traits in the genus Algansea, whereas the character states of the remaining six characters partially corroborated those hypotheses. Conclusion Monophyly of the genus Algansea was corroborated in this study. Tree topology shows the genus consists of three main lineages: Central-Eastern, Western, and Southern clades. However, the relationships among these clades remained unresolved. Congruence found between the available geological and climatic history and the divergence times made it possible to infer the biogeographical history of Algansea, which suggested that vicariance events were responsible for the evolutionary history of the genus. Interestingly, this pattern was shared with other members of the freshwater fish fauna of central Mexico. In addition, molecular data also show that some morphological traits alleged to represent synapomorphies in previous studies were actually homoplasies. Others traits were corroborated as synapomorphies, particularly in those species of a subgroup corresponding with the Central-Eastern clade within Algansea; this corroboration is interpreted as a result of evolutionary adaptations. PMID:19735558

New data on the presence of hemocyanin in Plecoptera: recomposing a puzzle.

PubMed

Amore, Valentina; Gaetani, Brunella; Puig, Maria Angeles; Fochetti, Romolo

2011-01-01

The specific role of hemocyanin in Plecoptera (stoneflies) is still not completely understood, since none of the hypotheses advanced have proven fully convincing. Previous data show that mRNA hemocyanin sequences are not present in all Plecoptera, and that hemocyanin does not seem to be uniformly distributed within the order. All species possess hexamerins, which are multifunction proteins that probably originated from hemocyanin. In order to obtain an increasingly detailed picture on the presence and distribution of hemocyanin across the order, this study presents new data regarding nymphs and adults of selected Plecoptera species. Results confirm that the hemocyanin expression differs among nymphs in the studied stonefly species. Even though previous studies have found hemocyanin in adults of two stonefly species it was not detected in the present study, even in species where nymphs show hemocyanin, suggesting that the physiological need of this protein can change during life cycle. The phylogenetic pattern obtained using hemocyanin sequences matches the accepted scheme of traditional phylogeny based on morphology, anatomy, and biology. It is remarkable to note that the hemocyanin conserved region acts like a phylogenetic molecular marker within Plecoptera.

Serotonin transporter gene influences the time course of improvement of "core" depressive and somatic anxiety symptoms during treatment with SSRIs for recurrent mood disorders.

PubMed

Serretti, Alessandro; Mandelli, Laura; Lorenzi, Cristina; Pirovano, Adele; Olgiati, Paolo; Colombo, Cristina; Smeraldi, Enrico

2007-01-15

The short variant of the serotonin transporter gene (SERTPR) has been consistently associated with a poorer response to treatment with various selective serotonin reuptake inhibitors (SSRIs). Antidepressant response is not a unitary phenomenon, however, and we here hypothesized that the SERTPR effect could be specific to some types of symptomatology. The sample comprised 281 inpatients affected by mood disorders and treated for major depression with SSRIs. The total depressive scores for all patients were analyzed in previous reports, but symptomatologic clusters were not examined previously. The 21-item Hamilton Rating Scale for Depression (HAM-D) was administered to evaluate depressive symptoms at baseline and weekly over 6 weeks of treatment. All patients were genotyped for the SERTPR polymorphism. Compared with patients with the SERTPR l/l and l/s polymorphisms, s/s patients showed a selective and slower improvement of depressive "core" and somatic anxiety symptoms, but they did not differ from other patients regarding other symptomatologic clusters such as insomnia and motor retardation. These findings support the view that response to SSRIs is not a unitary phenomenon and that improvement of symptomatologic clusters as, at least in part, genetically driven. SERTPR may be hypothesized as concurrently participating to the activity of anatomic brain regions differentially involved in depression and somatic symptoms of anxiety; however, further studies are required to examine these complex interactions.

[Consumer's psychological processes of hoarding and avoidant purchasing after the Tohoku earthquake].

PubMed

Ohtomo, Shoji; Hirose, Yukio

2014-02-01

This study examined psychological processes of consumers that had determined hoarding and avoidant purchasing behaviors after the Tohoku earthquake within a dual-process model. The model hypothesized that both intentional motivation based on reflective decision and reactive motivation based on non-reflective decision predicted the behaviors. This study assumed that attitude, subjective norm and descriptive norm in relation to hoarding and avoidant purchasing were determinants of motivations. Residents in the Tokyo metropolitan area (n = 667) completed internet longitudinal surveys at three times (April, June, and November, 2011). The results indicated that intentional and reactive motivation determined avoidant purchasing behaviors in June; only intentional motivation determined the behaviors in November. Attitude was a main determinant of the motivations each time. Moreover, previous behaviors predicted future behaviors. In conclusion, purchasing behaviors were intentional rather than reactive behaviors. Furthermore, attitude and previous behaviors were important determinants in the dual-process model. Attitude and behaviors formed in April continued to strengthen the subsequent decisions of purchasing behavior.

Greater loss of object than spatial mnemonic discrimination in aged adults.

PubMed

Reagh, Zachariah M; Ho, Huy D; Leal, Stephanie L; Noche, Jessica A; Chun, Amanda; Murray, Elizabeth A; Yassa, Michael A

2016-04-01

Previous studies across species have established that the aging process adversely affects certain memory-related brain regions earlier than others. Behavioral tasks targeted at the function of vulnerable regions can provide noninvasive methods for assessing the integrity of particular components of memory throughout the lifespan. The present study modified a previous task designed to separately but concurrently test detailed memory for object identity and spatial location. Memory for objects or items is thought to rely on perirhinal and lateral entorhinal cortices, among the first targets of Alzheimer's related neurodegeneration. In line with prior work, we split an aged adult sample into "impaired" and "unimpaired" groups on the basis of a standardized word-learning task. The "impaired" group showed widespread difficulty with memory discrimination, whereas the "unimpaired" group showed difficulty with object, but not spatial memory discrimination. These findings support the hypothesized greater age-related impacts on memory for objects or items in older adults, perhaps even with healthy aging. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.

Ecologic Niche Modeling and Potential Reservoirs for Chagas Disease, Mexico.

PubMed Central

Sánchez-Cordero, Victor; Ben Beard, C.; Ramsey, Janine M.

2002-01-01

Ecologic niche modeling may improve our understanding of epidemiologically relevant vector and parasite-reservoir distributions. We used this tool to identify host relationships of Triatoma species implicated in transmission of Chagas disease. Associations have been documented between the protracta complex (Triatoma: Triatominae: Reduviidae) with packrat species (Neotoma spp.), providing an excellent case study for the broader challenge of developing hypotheses of association. Species pairs that were identified coincided exactly with those in previous studies, suggesting that local interactions between Triatoma and Neotoma species and subspecies have implications at a geographic level. Nothing is known about sylvatic associates of T. barberi, which are considered the primary Chagas vector in Mexico; its geographic distribution coincided closely with that of N. mexicana, suggesting interaction. The presence of the species was confirmed in two regions where it had been predicted but not previously collected. This approach may help in identifying Chagas disease risk areas, planning vector-control strategies, and exploring parasite-reservoir associations for other emerging diseases. PMID:12095431

Evaluation of six holmium:YAG optical fibers for ureteroscopy: What's new in 2009?

NASA Astrophysics Data System (ADS)

Knudsen, Bodo E.; Teichman, Joel M. H.

2010-02-01

The holmium:yttrium aluminum garnet (YAG) laser is the gold standard laser for intracorporeal lithotripsy.1 Optical fibers are utilized to transmit laser energy to the surface of a stone for fragmentation via a predominant photothermal mechanism.2 Previous work has demonstrated that performance characteristics of holmium:YAG optical fibers used for laser lithotripsy varies. Performance may difference not only between fibers made by different manufacturers but also between individual fibers produced by the same manufacturer.3,4 Fiber failure with bending, such as during lower pole ureterorenoscopy, can lead to catastrophic endoscope damage resulting in costly repair. Manufacturers continue to develop new holmium:YAG optical fibers. In this study we evaluate a series of newly commercially available fibers using a previously designed testing protocol. This study was designed to determine the performance and threshold for failure of six newly available holmium:YAG laser fibers from Cook Medical and Fibertech Gmbh. We hypothesize that fiber performance will continue to vary amongst different holmium:YAG optical fibers.

The Effect of Representations on Difficulty Perception and Learning of the Physical Concept of Pressure

ERIC Educational Resources Information Center

Corradi, David M. J.; De Jaegher, Christophe; Juarez-Collazo, Norma A.; Elen, Jan; Clarebout, Geraldine

2013-01-01

Previous research indicates that when learners divide their attention over different sources of information (representations), learners perceive the information as more difficult and have a harder time increasing their understanding. This can be overcome by integrating representations. In this research, using 85 participants, we hypothesized that…

THYROID HORMONES AND NERVOUS SYSTEM DEVELOPMENT: SITE-OF-ACTION AND RELEVANCE OF AN ANIMAL MODEL OF DEVELOPMENTAL HYPYOTHYROXINEMIA-INDUCED HEARING LOSS.

EPA Science Inventory

Previous research demonstrated that perinatal exposure to Aroclor 1254 (A1254) resulted in both hypothyroxinemia (HPX) and a low-frequency ototoxicity (hearing loss). We hypothesized that the ototoxicity resulted from A1254- induced HPX during the postnatal critical period of c...

The Effect of Normative and Behavioral Persuasion on Help Seeking in Thai and American College Students

ERIC Educational Resources Information Center

Christopher, Michael S.; Skillman, Gemma D.; Kirkhart, Matthew W.; D'Souza, June B.

2006-01-01

On the basis of previous research on self-construals, the theory of reasoned action, and persuasive communication, the authors hypothesized that individual, behavioral-focused information would be more effective in increasing help-seeking intention among college students in the United States, whereas relational, normative-focused information would…

Geostatistical Modeling of the Spatial Distribution of Sediment Oxygen Demand Within a Coastal Plain Blackwater Watershed

USDA-ARS?s Scientific Manuscript database

Blackwater streams of the Georgia Coastal Plain are often listed as impaired due to chronically low DO levels. Previous research has shown that high sediment oxygen demand (SOD) values, a hypothesized cause of lowered DO within these waters, are significantly positively correlated with TOC within th...

Sex Differences in the Experience of Widowhood.

ERIC Educational Resources Information Center

Barrett, Carol J.

Previous writers have presumed that widowhood is more stressful for one sex or the other. Hypotheses derived from demographic considerations and sex role developmental theory compared the needs and resources of 147 widows and 42 widowers, relative to 190 married persons. All subjects were non-institutionalized urban residents aged 62 or over. The…

Executive Control and the Experience of Regret

ERIC Educational Resources Information Center

Burns, Patrick; Riggs, Kevin J.; Beck, Sarah R.

2012-01-01

The experience of regret rests on a counterfactual analysis of events. Previous research indicates that regret emerges at around 6 years of age, marginally later than the age at which children begin to answer counterfactual questions correctly. We hypothesized that the late emergence of regret relative to early counterfactual thinking is a result…

The Aggression-Inhibiting and Aggression-Facilitating Influence of Heightened Sexual Arousal.

ERIC Educational Resources Information Center

Baron, Robert A.; Bell, Paul A.

Eighty-six undergraduate males participated in an experiment designed to investigate the impact of various types of erotic stimuli upon aggression. On the basis of previous research, it was hypothesized that exposure to mild erotic stimuli would tend to inhibit subsequent aggression, while exposure to more arousing stimuli of this type would…

In the Eye of the Beholder: Emotional Labor in Academia Varies with Tenure and Gender

ERIC Educational Resources Information Center

Tunguz, Sharmin

2016-01-01

Expanding from the customer-service perspective, the present research investigated emotional labor, defined as "service with authority," in an academic context. Drawing from previous research on display rules and power, tenure and gender were hypothesized to influence the extent to which college faculty labored to provide "service…

Issues in Proposing a General Model of the Effects of Divorce on Children.

ERIC Educational Resources Information Center

Kurdek, Lawrence A.

1993-01-01

Responds to previous article by Amato on children's adjustment to divorce. Focuses on two aspects of Amato's review: the mechanics of the review (perspectives advanced, criteria used to evaluate generated hypotheses, and accuracy of conclusions) and critical comments raised about the existing literature and in particular the proposed general model…

Reasoning Maps: A Generally Applicable Method for Characterizing Hypothesis-Testing Behaviour. Research Report

ERIC Educational Resources Information Center

White, Brian

2004-01-01

This paper presents a generally applicable method for characterizing subjects' hypothesis-testing behaviour based on a synthesis that extends on previous work. Beginning with a transcript of subjects' speech and videotape of their actions, a Reasoning Map is created that depicts the flow of their hypotheses, tests, predictions, results, and…

An Economic Theory of School Governance.

ERIC Educational Resources Information Center

Rada, Roger D.

Working from the basic assumption that the primary motivation for those involved in school governance is self-interest, this paper develops and discusses 15 hypotheses that form the essential elements of an economic theory of school governance. The paper opens with a review of previous theories of governance and their origins in social science…

The Relationship between Object Files and Conscious Perception

ERIC Educational Resources Information Center

Mitroff, S.R.; Scholl, B.J.; Wynn, K.

2005-01-01

Object files (OFs) are hypothesized mid-level representations which mediate our conscious perception of persisting objects-e.g. telling us 'which went where'. Despite the appeal of the OF framework, not previous research has directly explored whether OFs do indeed correspond to conscious percepts. Here we present at least one case wherein…

Predisaster Trait Anxiety and Negative Affect Predict Posttraumatic Stress in Youths after Hurricane Katrina

ERIC Educational Resources Information Center

Weems, Carl F.; Pina, Armando A.; Costa, Natalie M.; Watts, Sarah E.; Taylor, Leslie K.; Cannon, Melinda F.

2007-01-01

On the basis of theory and previous research, it was hypothesized that predisaster child trait anxiety would predict disaster-related posttraumatic stress symptoms and generalized anxiety disorder symptoms, even after controlling for the number of hurricane exposure events. Results support this hypothesis and further indicate that predisaster…

The Effects of Classroom Autonomy, Staff Collegiality, and Administrative Support on Teachers' Job Satisfaction

ERIC Educational Resources Information Center

Lasseter, Austin

2013-01-01

The purpose of my dissertation is to determine which job-related factors are most likely to explain teachers' sense of satisfaction with their current job. Based on previous research (Fairchild et al., 2012; Lee, Dedrick, & Smith, 1991; Perie & Baker, 1997), I hypothesized that teachers' perceptions of classroom autonomy, staff…

Apo-10'-lycopenoic acid inhibits cancer cell migration and angiogenesis and induces peroxisome proliferator-activated receptor gamma

USDA-ARS?s Scientific Manuscript database

Scope: We have previously shown that apo-10'-lycopenoic acid (ALA), a derivative of lycopene through cleavage by carotene-9',10'-oxygenase, inhibits tumor progression and metastasis in both liver and lung cancer animal models. The underlying mechanism remains unknown. We hypothesized that ALA inhibi...

Dollars, Dependency, and Divorce: Four Perspectives on the Role of Wives Income

ERIC Educational Resources Information Center

Rogers, Stacy J.

2004-01-01

This article delineates and assesses the evidence for four perspectives that have guided previous research on the relationship between wives economic resources and marital stability. Hypotheses from these perspectives were tested using event history methods and 1980-1997 panel data for 1,704 individuals from the Marital Instability Over the Life…

Mindfulness, Authentic Functioning, and Work Engagement: A Growth Modeling Approach

ERIC Educational Resources Information Center

Leroy, Hannes; Anseel, Frederik; Dimitrova, Nicoletta G.; Sels, Luc

2013-01-01

Previous research has demonstrated that mindfulness helps reduce symptoms of work stress but research has yet to clarify "whether" and "how" mindfulness is linked to work engagement. Using self-determination theory we hypothesize that mindfulness is positively related to work engagement and that this relationship can be better understood through…

Homosexual Fellatio: Erect Penis Licking between Male Bonin Flying Foxes Pteropus pselaphon.

PubMed

Sugita, Norimasa

2016-01-01

A recent focus of interest has been on the functional significance of genital licking (fellatio and cunnilingus) in relation to sexual selection in Pteropodid bats. In the present paper, a form of fellatio in wild Bonin flying foxes, Pteropus pselaphon, performed between adult males has been reported. During the mating season, adult flying foxes roost in same-sex groups, forming ball-shaped clusters which provide warmth. The female clusters may also contain a few males. Unassociated with allogrooming, same-sex genital licking occurred among males in the all male clusters. As such, male-male fellatio can be considered as homosexual behavior, two functional explanations could account for this behavior; the social bonding and the social tension regulation hypotheses suggested in a previous review. Given that neither the simpler alternative that in all male groups such fellatio may represent misdirected sexual behavior, nor the two previously proposed functional hypotheses were supported by the data, I propose another functional hypothesis. Homosexual fellatio in this species could help males solve inconsistent situations in the roost when there are conflicts between cooperative behavior for social thermoregulation and competition for mating.

A Model-Based Approach for Identifying Signatures of Ancient Balancing Selection in Genetic Data

PubMed Central

DeGiorgio, Michael; Lohmueller, Kirk E.; Nielsen, Rasmus

2014-01-01

While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates. PMID:25144706

A model-based approach for identifying signatures of ancient balancing selection in genetic data.

PubMed

DeGiorgio, Michael; Lohmueller, Kirk E; Nielsen, Rasmus

2014-08-01

While much effort has focused on detecting positive and negative directional selection in the human genome, relatively little work has been devoted to balancing selection. This lack of attention is likely due to the paucity of sophisticated methods for identifying sites under balancing selection. Here we develop two composite likelihood ratio tests for detecting balancing selection. Using simulations, we show that these methods outperform competing methods under a variety of assumptions and demographic models. We apply the new methods to whole-genome human data, and find a number of previously-identified loci with strong evidence of balancing selection, including several HLA genes. Additionally, we find evidence for many novel candidates, the strongest of which is FANK1, an imprinted gene that suppresses apoptosis, is expressed during meiosis in males, and displays marginal signs of segregation distortion. We hypothesize that balancing selection acts on this locus to stabilize the segregation distortion and negative fitness effects of the distorter allele. Thus, our methods are able to reproduce many previously-hypothesized signals of balancing selection, as well as discover novel interesting candidates.

Use of optical tweezers to probe epithelial mechanosensation

NASA Astrophysics Data System (ADS)

Resnick, Andrew

2010-01-01

Cellular mechanosensation mechanisms have been implicated in a variety of disease states. Specifically in renal tubules, the primary cilium and associated mechanosensitive ion channels are hypothesized to play a role in water and salt homeostasis, with relevant disease states including polycystic kidney disease and hypertension. Previous experiments investigating ciliary-mediated cellular mechanosensation have used either fluid flow chambers or micropipetting to elicit a biological response. The interpretation of these experiments in terms of the ``ciliary hypothesis'' has been difficult due the spatially distributed nature of the mechanical disturbance-several competing hypotheses regarding possible roles of primary cilium, glycocalyx, microvilli, cell junctions, and actin cytoskeleton exist. I report initial data using optical tweezers to manipulate individual primary cilia in an attempt to elicit a mechanotransduction response-specifically, the release of intracellular calcium. The advantage of using laser tweezers over previous work is that the applied disturbance is highly localized. I find that stimulation of a primary cilium elicits a response, while stimulation of the apical surface membrane does not. These results lend support to the hypothesis that the primary cilium mediates transduction of mechanical strain into a biochemical response in renal epithelia.

Agave Chewing and Dental Wear: Evidence from Quids

PubMed Central

Hammerl, Emily E.; Baier, Melissa A.; Reinhard, Karl J.

2015-01-01

Agave quid chewing is examined as a potential contributing behavior to hunter-gatherer dental wear. It has previously been hypothesized that the contribution of Agave quid chewing to dental wear would be observed in communities wherever phytolith-rich desert succulents were part of subsistence. Previous analysis of coprolites from a prehistoric agricultural site, La Cueva de los Muertos Chiquitos in Durango, Mexico, showed that Agave was a consistent part of a diverse diet. Therefore, quids recovered at this site ought to be useful materials to test the hypothesis that dental wear was related to desert succulent consumption. The quids recovered from the site were found to be largely derived from chewing Agave. In this study, the quids were found to be especially rich in phytoliths, and analysis of dental casts made from impressions left in the quids revealed flat wear and dental attrition similar to that of Agave-reliant hunter-gatherers. Based on evidence obtained from the analysis of quids, taken in combination with results from previous studies, it is determined that Agave quid chewing was a likely contributing factor to dental wear in this population. As such, our method provides an additional avenue of dental research in areas where quids are present. PMID:26230855

Deep Sequencing of 71 Candidate Genes to Characterize Variation Associated with Alcohol Dependence.

PubMed

Clark, Shaunna L; McClay, Joseph L; Adkins, Daniel E; Kumar, Gaurav; Aberg, Karolina A; Nerella, Srilaxmi; Xie, Linying; Collins, Ann L; Crowley, James J; Quackenbush, Corey R; Hilliard, Christopher E; Shabalin, Andrey A; Vrieze, Scott I; Peterson, Roseann E; Copeland, William E; Silberg, Judy L; McGue, Matt; Maes, Hermine; Iacono, William G; Sullivan, Patrick F; Costello, Elizabeth J; van den Oord, Edwin J

2017-04-01

Previous genomewide association studies (GWASs) have identified a number of putative risk loci for alcohol dependence (AD). However, only a few loci have replicated and these replicated variants only explain a small proportion of AD risk. Using an innovative approach, the goal of this study was to generate hypotheses about potentially causal variants for AD that can be explored further through functional studies. We employed targeted capture of 71 candidate loci and flanking regions followed by next-generation deep sequencing (mean coverage 78X) in 806 European Americans. Regions included in our targeted capture library were genes identified through published GWAS of alcohol, all human alcohol and aldehyde dehydrogenases, reward system genes including dopaminergic and opioid receptors, prioritized candidate genes based on previous associations, and genes involved in the absorption, distribution, metabolism, and excretion of drugs. We performed single-locus tests to determine if any single variant was associated with AD symptom count. Sets of variants that overlapped with biologically meaningful annotations were tested for association in aggregate. No single, common variant was significantly associated with AD in our study. We did, however, find evidence for association with several variant sets. Two variant sets were significant at the q-value <0.10 level: a genic enhancer for ADHFE1 (p = 1.47 × 10 -5 ; q = 0.019), an alcohol dehydrogenase, and ADORA1 (p = 5.29 × 10 -5 ; q = 0.035), an adenosine receptor that belongs to a G-protein-coupled receptor gene family. To our knowledge, this is the first sequencing study of AD to examine variants in entire genes, including flanking and regulatory regions. We found that in addition to protein coding variant sets, regulatory variant sets may play a role in AD. From these findings, we have generated initial functional hypotheses about how these sets may influence AD. Copyright © 2017 by the Research Society on Alcoholism.

Interest in STEM is contagious for students in biology, chemistry, and physics classes

PubMed Central

Hazari, Zahra; Potvin, Geoff; Cribbs, Jennifer D.; Godwin, Allison; Scott, Tyler D.; Klotz, Leidy

2017-01-01

We report on a study of the effect of peers’ interest in high school biology, chemistry, and physics classes on students’ STEM (science, technology, engineering, and mathematics)–related career intentions and course achievement. We define an interest quorum as a science class where students perceive a high level of interest for the subject matter from their classmates. We hypothesized that students who experience such an interest quorum are more likely to choose STEM careers. Using data from a national survey study of students‘ experiences in high school science, we compared the effect of five levels of peer interest reported in biology, chemistry, and physics courses on students‘ STEM career intentions. The results support our hypothesis, showing a strong, positive effect of an interest quorum even after controlling for differences between students that pose competing hypotheses such as previous STEM career interest, academic achievement, family support for mathematics and science, and gender. Smaller positive effects of interest quorums were observed for course performance in some cases, with no detrimental effects observed across the study. Last, significant effects persisted even after controlling for differences in teaching quality. This work emphasizes the likely importance of interest quorums for creating classroom environments that increase students’ intentions toward STEM careers while enhancing or maintaining course performance. PMID:28808678

Career interest, self-efficacy, and perception in undecided and nursing undergraduate students: a quantitative study.

PubMed

Fillman, Valentina M

2015-01-01

Career choice variables of career interest, self-efficacy, and perception were chosen based upon Social Cognitive Career Theory concepts for study between nursing and undecided undergraduate student groups. Components of the Career Search Questionnaire and Perceptions of Professional Nursing instruments were combined and adapted to form the Career Choice Survey for use in this research. This web-based survey totaling 40 questions was sent to 577 undergraduate students with a 12% response rate (N=68). Due to the need to increase nursing recruitment and retention, hypotheses were developed that distinguish if any relationship existed between groups. Findings of this quantitative study resulted in statistically significant results on two of the three variable hypotheses (p=.006 for career interest, p=.002 for self-efficacy, p=.395 for perception), aligning with previous research and provide insight into the change in nursing perception. Overall, scores for each subscale were encouraging to current nurses and expected from undecided students. Implications for practice include increases in accurate nursing portrayal in the media and early career counseling to younger populations. Nurse educators can further research in career choice with focus on continuing education for current nurses and recruitment of young nursing hopefuls. Copyright © 2014 Elsevier Ltd. All rights reserved.

Interest in STEM is contagious for students in biology, chemistry, and physics classes.

PubMed

Hazari, Zahra; Potvin, Geoff; Cribbs, Jennifer D; Godwin, Allison; Scott, Tyler D; Klotz, Leidy

2017-08-01

We report on a study of the effect of peers' interest in high school biology, chemistry, and physics classes on students' STEM (science, technology, engineering, and mathematics)-related career intentions and course achievement. We define an interest quorum as a science class where students perceive a high level of interest for the subject matter from their classmates. We hypothesized that students who experience such an interest quorum are more likely to choose STEM careers. Using data from a national survey study of students' experiences in high school science, we compared the effect of five levels of peer interest reported in biology, chemistry, and physics courses on students' STEM career intentions. The results support our hypothesis, showing a strong, positive effect of an interest quorum even after controlling for differences between students that pose competing hypotheses such as previous STEM career interest, academic achievement, family support for mathematics and science, and gender. Smaller positive effects of interest quorums were observed for course performance in some cases, with no detrimental effects observed across the study. Last, significant effects persisted even after controlling for differences in teaching quality. This work emphasizes the likely importance of interest quorums for creating classroom environments that increase students' intentions toward STEM careers while enhancing or maintaining course performance.

Facebook and MySpace: complement or substitute for face-to-face interaction?

PubMed

Kujath, Carlyne L

2011-01-01

Previous studies have claimed that social-networking sites are used as a substitute for face-to-face interaction, resulting in deteriorating relationship quality and decreased intimacy among its users. The present study hypothesized that this type of communication is not a substitute for face-to-face interaction; rather, that it is an extension of communication with face-to-face partners. A survey was administered to examine the use of Facebook and MySpace in this regard among 183 college students. The study confirmed that Facebook and MySpace do act as an extension of face-to-face interaction, but that some users do tend to rely on Facebook and MySpace for interpersonal communication more than face-to-face interaction.

Meditation reduces pain-related neural activity in the anterior cingulate cortex, insula, secondary somatosensory cortex, and thalamus

PubMed Central

Nakata, Hiroki; Sakamoto, Kiwako; Kakigi, Ryusuke

2014-01-01

Recent studies have shown that meditation inhibits or relieves pain perception. To clarify the underlying mechanisms for this phenomenon, neuroimaging methods, such as functional magnetic resonance imaging, and neurophysiological methods, such as magnetoencephalography and electroencephalography, have been used. However, it has been difficult to interpret the results, because there is some paradoxical evidence. For example, some studies reported increased neural responses to pain stimulation during meditation in the anterior cingulate cortex (ACC) and insula, whereas others showed a decrease in these regions. There have been inconsistent findings to date. Moreover, in general, since the activities of the ACC and insula are correlated with pain perception, the increase in neural activities during meditation would be related to the enhancement of pain perception rather than its reduction. These contradictions might directly contribute to the ‘mystery of meditation.’ In this review, we presented previous findings for brain regions during meditation and the anatomical changes that occurred in the brain with long-term meditation training. We then discussed the findings of previous studies that examined pain-related neural activity during meditation. We also described the brain mechanisms responsible for pain relief during meditation, and possible reasons for paradoxical evidence among previous studies. By thoroughly overviewing previous findings, we hypothesized that meditation reduces pain-related neural activity in the ACC, insula, secondary somatosensory cortex, and thalamus. We suggest that the characteristics of the modulation of this activity may depend on the kind of meditation and/or number of years of experience of meditation, which were associated with paradoxical findings among previous studies that investigated pain-related neural activities during meditation. PMID:25566158

Insights into Holocene megafauna survival and extinction in southeastern Brazil from new AMS 14C dates

NASA Astrophysics Data System (ADS)

Hubbe, Alex; Hubbe, Mark; Karmann, Ivo; Cruz, Francisco W.; Neves, Walter A.

2013-03-01

The extinction of late Quaternary megafauna in South America has been extensively debated in past decades. The majority of the hypotheses explaining this phenomenon argue that the extinction was the result of human activities, environmental changes, or even synergism between the two. Although still limited, a good chronological framework is imperative to discuss the plausibility of the available hypotheses. Here we present six new direct AMS 14C radiocarbon dates from the state of São Paulo (Brazil) to further characterize the chronological distribution of extinct fauna in this part of South America. The new dates make evident that ground sloths, toxodonts, and saber-toothed cats lived in the region around the Pleistocene/Holocene transition, and, in agreement with previous studies, also suggest an early Holocene survival for the ground sloth Catonyx cuvieri. Taken together with local paleoclimatic and archaeological data, the new dates do not support hunting or indirect human activities as a major cause for megafauna extinction. Although more data are required, parsimony suggests that climatic changes played a major role in this extinction event.

Child Characteristics and Parental Educational Expectations: Evidence for Transmission with Transaction

PubMed Central

Briley, Daniel A.; Harden, K. Paige; Tucker-Drob, Elliot M.

2014-01-01

Parents’ expectations for their children’s ultimate educational attainment have been hypothesized to play an instrumental role in socializing academically-relevant child behaviors, beliefs, and abilities. In addition to social transmission of educationally relevant values from parents to children, parental expectations and child characteristics may transact bidirectionally. We explore this hypothesis using both longitudinal and genetically informative twin data from the Early Childhood Longitudinal Study –Birth and Kindergarten cohorts. Our behavior genetic results indicate that parental expectations partly reflect child genetic variation, even as early as 4 years of age. Two classes of child characteristics were hypothesized to contribute to these child-to-parent effects: behavioral tendencies (approaches toward learning and problem behaviors) and achievement (math and reading). Using behavior genetic models, we find within-twin-pair associations between these child characteristics and parental expectations. Using longitudinal cross-lagged models, we find that initial variation in child characteristics predicts future educational expectations above and beyond previous educational expectations. These results are consistent with transactional frameworks in which parent-to-child and child-to-parent effects co-occur. PMID:25285965

Effective geoscience pedagogy at the undergraduate level

NASA Astrophysics Data System (ADS)

Warden, Kelsey

This investigation used constructivist pedagogical methods within the framework of an introductory level undergraduate geoscience course to gauge both the changes in attitude and cognition of students. Pedagogy was modified in the laboratory setting, but maintained in the lecture setting and homework. Curriculum was also maintained in the lecture, but was changed in the laboratory to emphasize the large concepts and systems stressed in Earth Science Literacy Principles. Student understanding of these concepts and systems was strengthened by factual knowledge, but recall and memorization were not the goal of the laboratory instruction. The overall goal of the study was to build student understanding more effectively than in previous semesters such that the students would become Earth Science literate adults. We hypothesized that a healthy comprehension of the connections between the human population and Earth's systems would lead to improved cognition and attitude toward Earth Science. This was tested using pre- and post-testing of attitudes via an anonymous survey on the first and last days of the laboratory, student responses to the end-of-course evaluations, and student performance on early-semester and late-semester content testing. The results support the hypotheses.

Mechanisms linking authentic leadership to emotional exhaustion: The role of procedural justice and emotional demands in a moderated mediation approach.

PubMed

Kampa, Judith; Rigotti, Thomas; Otto, Kathleen

2017-04-07

In order to gain more knowledge on how the positive leadership concept of authentic leadership impacts follower strain, this study tries to uncover procedural justice as an underlying mechanism. In contrast to previous work, we exclusively base our theoretical model on justice theories. Specifically, we hypothesize that authentic leadership negatively predicts emotional exhaustion through perceptions of procedural justice. We assume that this indirect effect is conditional on followers' amount of emotional demands, and that the procedural justice-emotional exhaustion relationship is stronger when emotional demands are high. This finally results in a stronger exhaustion-reducing effect of authentic leadership. The proposed moderated mediation model was tested in a sample of N=628 employees nested in 168 teams using lagged data from three waves. Results provide support for all hypotheses. Authentic leadership is critical to employees' well-being as it contributes to an elevated perception of positive work conditions (procedural justice), especially in contexts with high emotional demands. Limitations and practical implications on leadership development are discussed.

Prediction of exercise in patients across various stages of bariatric surgery: a comparison of the merits of the theory of reasoned action versus the theory of planned behavior.

PubMed

Hunt, Hillary R; Gross, Alan M

2009-11-01

Obesity is a world-wide health concern approaching epidemic proportions. Successful long-term treatment involves a combination of bariatric surgery, diet, and exercise. Social cognitive models, such as the Theory of Reasoned Action (TRA) and the Theory of Planned Behavior (TPB), are among the most commonly tested theories utilized in the prediction of exercise. As exercise is not a completely volitional behavior, it is hypothesized that the TPB is a superior theoretical model for the prediction of exercise intentions and behavior. This study tested validity of the TPB in a sample of bariatric patients and further validated its improvement over the TRA in predicting exercise adherence at different operative stages. Results generally confirmed research hypotheses. Superiority of the TPB model was validated in this sample of bariatric patients, and Perceived Behavioral Control emerged as the single-best predictor of both exercise intentions and self-reported behavior. Finally, results suggested that both subjective norms and attitudes toward exercise played a larger role in the prediction of intention and behavior than previously reported.

Learning by (video) example: a randomized study of communication skills training for end-of-life and error disclosure family care conferences.

PubMed

Schmitz, Connie C; Braman, Jonathan P; Turner, Norman; Heller, Stephanie; Radosevich, David M; Yan, Yelena; Miller, Jane; Chipman, Jeffrey G

2016-11-01

Teaching residents to lead end of life (EOL) and error disclosure (ED) conferences is important. We developed and tested an intervention using videotapes of EOL and error disclosure encounters from previous Objective Structured Clinical Exams. Residents (n = 72) from general and orthopedic surgery programs at 2 sites were enrolled. Using a prospective, pre-post, block group design with stratified randomization, we hypothesized the treatment group would outperform the control on EOL and ED cases. We also hypothesized that online course usage would correlate positively with post-test scores. All residents improved (pre-post). At the group level, treatment effects were insignificant, and post-test performance was unrelated to course usage. At the subgroup level for EOL, low performers assigned to treatment scored higher than controls at post-test; and within the treatment group, post graduate year 3 residents outperformed post graduate year ​1 residents. To be effective, online curricula illustrating communication behaviors need face-to-face interaction, individual role play with feedback and discussion. Copyright © 2016 Elsevier Inc. All rights reserved.

Perceptions of adolescent bullying: attributions of blame and responsibility in cases of cyber-bullying.

PubMed

Morrow, Allison; Downey, Christina A

2013-12-01

Cyber-bullying (where victims are targeted via online social networking or other electronic means) has gained increased attention in research and the broadcast media, but previous research has not investigated attribution of blame in such cyber-bullying events. This experiment hypothesized that participants would assign higher ratings of blame to bullying perpetrators when the bullying situations were depicted as having highly foreseeable outcomes (vs. unforeseeable outcomes), and as occurring in school (vs. online). In addition, a significant interaction was predicted between outcome foreseeability and bullying situation, with highly foreseeable in-school events being rated as the most predictable and attributable to the bully's actions. One-hundred sixty-three participants completed surveys containing demographic items, items regarding their past experiences of victimization, and one of four randomly-assigned vignettes detailing a bullying situation (which participants rated). While hypotheses regarding outcome foreseeability were supported, no cyber-bullying vs. in-school main effects (or corresponding interaction effects) were detected. Implications for future research and practice, as well as study limitations, are discussed. © 2013 The Scandinavian Psychological Associations.

Mechanisms linking authentic leadership to emotional exhaustion: The role of procedural justice and emotional demands in a moderated mediation approach

PubMed Central

KAMPA, Judith; RIGOTTI, Thomas; OTTO, Kathleen

2016-01-01

In order to gain more knowledge on how the positive leadership concept of authentic leadership impacts follower strain, this study tries to uncover procedural justice as an underlying mechanism. In contrast to previous work, we exclusively base our theoretical model on justice theories. Specifically, we hypothesize that authentic leadership negatively predicts emotional exhaustion through perceptions of procedural justice. We assume that this indirect effect is conditional on followers’ amount of emotional demands, and that the procedural justice-emotional exhaustion relationship is stronger when emotional demands are high. This finally results in a stronger exhaustion-reducing effect of authentic leadership. The proposed moderated mediation model was tested in a sample of N=628 employees nested in 168 teams using lagged data from three waves. Results provide support for all hypotheses. Authentic leadership is critical to employees’ well-being as it contributes to an elevated perception of positive work conditions (procedural justice), especially in contexts with high emotional demands. Limitations and practical implications on leadership development are discussed. PMID:27818452

Child characteristics and parental educational expectations: evidence for transmission with transaction.

PubMed

Briley, Daniel A; Harden, K Paige; Tucker-Drob, Elliot M

2014-12-01

Parents' expectations for their children's ultimate educational attainment have been hypothesized to play an instrumental role in socializing academically relevant child behaviors, beliefs, and abilities. In addition to social transmission of educationally relevant values from parents to children, parental expectations and child characteristics may transact bidirectionally. We explore this hypothesis using both longitudinal and genetically informative twin data from the Early Childhood Longitudinal Study-Birth and Kindergarten cohorts. Our behavior genetic results indicate that parental expectations partly reflect child genetic variation, even as early as 4 years of age. Two classes of child characteristics were hypothesized to contribute to these child-to-parent effects: behavioral tendencies (approaches toward learning and problem behaviors) and achievement (math and reading). Using behavior genetic models, we find within-twin-pair associations between these child characteristics and parental expectations. Using longitudinal cross-lagged models, we find that initial variation in child characteristics predicts future educational expectations above and beyond previous educational expectations. These results are consistent with transactional frameworks in which parent-to-child and child-to-parent effects co-occur. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Maternal docosahexaenoic acid increases adiponectin and normalizes IUGR-induced changes in rat adipose deposition.

PubMed

Bagley, Heidi N; Wang, Yan; Campbell, Michael S; Yu, Xing; Lane, Robert H; Joss-Moore, Lisa A

2013-01-01

Intrauterine growth restriction (IUGR) predisposes to obesity and adipose dysfunction. We previously demonstrated IUGR-induced increased visceral adipose deposition and dysregulated expression of peroxisome proliferator activated receptor- γ 2 (PPAR γ 2) in male adolescent rats, prior to the onset of obesity. In other studies, activation of PPAR γ increases subcutaneous adiponectin expression and normalizes visceral adipose deposition. We hypothesized that maternal supplementation with docosahexaenoic acid (DHA), a PPAR γ agonist, would normalize IUGR adipose deposition in association with increased PPAR γ , adiponectin, and adiponectin receptor expression in subcutaneous adipose. To test these hypotheses, we used a well-characterized model of uteroplacental-insufficiency-(UPI-) induced IUGR in the rat with maternal DHA supplementation. Our primary findings were that maternal DHA supplementation during rat pregnancy and lactation (1) normalizes IUGR-induced changes in adipose deposition and visceral PPAR γ expression in male rats and (2) increases serum adiponectin, as well as adipose expression of adiponectin and adiponectin receptors in former IUGR rats. Our novel findings suggest that maternal DHA supplementation may normalize adipose dysfunction and promote adiponectin-induced improvements in metabolic function in IUGR.

The Weak Spots in Contemporary Science (and How to Fix Them).

PubMed

Wicherts, Jelte M

2017-11-27

In this review, the author discusses several of the weak spots in contemporary science, including scientific misconduct, the problems of post hoc hypothesizing (HARKing), outcome switching, theoretical bloopers in formulating research questions and hypotheses, selective reading of the literature, selective citing of previous results, improper blinding and other design failures, p-hacking or researchers' tendency to analyze data in many different ways to find positive (typically significant) results, errors and biases in the reporting of results, and publication bias. The author presents some empirical results highlighting problems that lower the trustworthiness of reported results in scientific literatures, including that of animal welfare studies. Some of the underlying causes of these biases are discussed based on the notion that researchers are only human and hence are not immune to confirmation bias, hindsight bias, and minor ethical transgressions. The author discusses solutions in the form of enhanced transparency, sharing of data and materials, (post-publication) peer review, pre-registration, registered reports, improved training, reporting guidelines, replication, dealing with publication bias, alternative inferential techniques, power, and other statistical tools.

Optimal stretching in the reacting wake of a bluff body.

PubMed

Wang, Jinge; Tithof, Jeffrey; Nevins, Thomas D; Colón, Rony O; Kelley, Douglas H

2017-12-01

We experimentally study spreading of the Belousov-Zhabotinsky reaction behind a bluff body in a laminar flow. Locations of reacted regions (i.e., regions with high product concentration) correlate with a moderate range of Lagrangian stretching and that range is close to the range of optimal stretching previously observed in topologically different flows [T. D. Nevins and D. H. Kelley, Phys. Rev. Lett. 117, 164502 (2016)]. The previous work found optimal stretching in a closed, vortex dominated flow, but this article uses an open flow and only a small area of appreciable vorticity. We hypothesize that optimal stretching is common in advection-reaction-diffusion systems with an excitation threshold, including excitable and bistable systems, and that the optimal range depends on reaction chemistry and not on flow shape or characteristic speed. Our results may also give insight into plankton blooms behind islands in ocean currents.

Spatial association between dissection density and environmental factors over the entire conterminous United States

NASA Astrophysics Data System (ADS)

Luo, Wei; Jasiewicz, Jaroslaw; Stepinski, Tomasz; Wang, Jinfeng; Xu, Chengdong; Cang, Xuezhi

2016-01-01

Previous studies of land dissection density (D) often find contradictory results regarding factors controlling its spatial variation. We hypothesize that the dominant controlling factors (and the interactions between them) vary from region to region due to differences in each region's local characteristics and geologic history. We test this hypothesis by applying a geographical detector method to eight physiographic divisions of the conterminous United States and identify the dominant factor(s) in each. The geographical detector method computes the power of determinant (q) that quantitatively measures the affinity between the factor considered and D. Results show that the factor (or factor combination) with the largest q value is different for physiographic regions with different characteristics and geologic histories. For example, lithology dominates in mountainous regions, curvature dominates in plains, and glaciation dominates in previously glaciated areas. The geographical detector method offers an objective framework for revealing factors controlling Earth surface processes.

The Moderating Role of Executive Functioning in Older Adults' Responses to a Reminder of Mortality

PubMed Central

Maxfield, Molly; Pyszczynski, Tom; Greenberg, Jeff; Pepin, Renee; Davis, Hasker P.

2011-01-01

In previous research, older adults responded to mortality salience (MS) with increased tolerance, whereas younger persons responded with increased punitiveness. One possible explanation for this is that many older adults adapt to challenges of later life, such as the prospect of mortality, by becoming more flexible. Recent studies suggest that positively-oriented adaptation is more likely for older adults with high levels of executive functioning. We thus hypothesized that the better an older adult's executive functioning, the more likely MS would result in increased tolerance. Older and younger adults were randomly assigned to MS or control conditions, and then evaluated moral transgressors. As in previous research, younger adults were more punitive following reminders of mortality; executive functioning did not affect their responses. Among older adults, high functioning individuals responded to MS with increased tolerance rather than intolerance, whereas those low in functioning became more punitive. PMID:21728445

Portuguese Version of the Pain Beliefs and Perceptions Inventory: A Multicenter Validation Study.

PubMed

Azevedo, Luís Filipe; Sampaio, Rute; Camila Dias, Cláudia; Romão, José; Lemos, Laurinda; Agualusa, Luís; Vaz-Serra, Sílvia; Patto, Teresa; Costa-Pereira, Altamiro; Castro-Lopes, José Manuel

2017-07-01

We aimed to perform the translation, cultural adaptation, and validation of the Pain Beliefs and Perceptions Inventory (PBPI) for the European Portuguese language and chronic pain population. This is a longitudinal multicenter validation study. A Portuguese version of the PBPI (PBPI-P) was created through a process of translation, back translation, and expert panel evaluation. The PBPI-P was administered to a total of 122 patients from 13 chronic pain clinics in Portugal, at baseline and after 7 days. Internal consistency and test-retest reliability were assessed by Cronbach's alpha (α) and intraclass correlation coefficient (ICC). Construct (convergent and discriminant) validity was assessed based on a set of previously developed theoretical hypotheses about interrelations between the PBPI-P and other measures. Exploratory and confirmatory factor analyses were performed to test the theoretical structure of the PBPI-P. The internal consistency and test-retest reliability coefficients for each respective subscale were α = 0.620 and ICC = 0.801 for mystery; α = 0.744 and ICC = 0.841 for permanence; α = 0.778 and ICC = 0.791 for constancy; and α = 0.764 and ICC = 0.881 for self-blame. Exploratory and confirmatory factor analysis revealed a four-factor structure (performance, constancy, self-blame, and mystery) that explained 63% of the variance. The construct validity of the PBPI-P was shown to be adequate, with more than 90% of the previously defined hypotheses regarding interrelations with other measures confirmed. The PBPI-P has been shown to be adequate and to have excellent reliability, internal consistency, and validity. It may contribute to a better pain assessment and is suitable for research and clinical use. © 2016 World Institute of Pain.

Exploring possible mechanisms of action for the nanotoxicity and protein binding of decorated nanotubes: interpretation of physicochemical properties from optimal QSAR models

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

Esposito, Emilio Xavier, E-mail: emilio@exeResearch.com; The Chem21 Group, Inc., 1780 Wilson Drive, Lake Forest, IL 60045; Hopfinger, Anton J., E-mail: hopfingr@gmail.com

2015-10-01

Carbon nanotubes have become widely used in a variety of applications including biosensors and drug carriers. Therefore, the issue of carbon nanotube toxicity is increasingly an area of focus and concern. While previous studies have focused on the gross mechanisms of action relating to nanomaterials interacting with biological entities, this study proposes detailed mechanisms of action, relating to nanotoxicity, for a series of decorated (functionalized) carbon nanotube complexes based on previously reported QSAR models. Possible mechanisms of nanotoxicity for six endpoints (bovine serum albumin, carbonic anhydrase, chymotrypsin, hemoglobin along with cell viability and nitrogen oxide production) have been extracted frommore » the corresponding optimized QSAR models. The molecular features relevant to each of the endpoint respective mechanism of action for the decorated nanotubes are also discussed. Based on the molecular information contained within the optimal QSAR models for each nanotoxicity endpoint, either the decorator attached to the nanotube is directly responsible for the expression of a particular activity, irrespective of the decorator's 3D-geometry and independent of the nanotube, or those decorators having structures that place the functional groups of the decorators as far as possible from the nanotube surface most strongly influence the biological activity. These molecular descriptors are further used to hypothesize specific interactions involved in the expression of each of the six biological endpoints. - Highlights: • Proposed toxicity mechanism of action for decorated nanotubes complexes • Discussion of the key molecular features for each endpoint's mechanism of action • Unique mechanisms of action for each of the six biological systems • Hypothesized mechanisms of action based on QSAR/QNAR predictive models.« less

A Structural Approach to Establishing a Platform Chemistry for the Tunable, Bulk Electron Beam Cross-Linking of Shape Memory Polymer Systems

PubMed Central

Hearon, Keith; Besset, Celine J.; Lonnecker, Alexander T.; Ware, Taylor; Voit, Walter E.; Wilson, Thomas S.; Wooley, Karen L.; Maitland, Duncan J.

2014-01-01

The synthetic design and thermomechanical characterization of shape memory polymers (SMPs) built from a new polyurethane chemistry that enables facile, bulk and tunable cross-linking of low-molecular weight thermoplastics by electron beam irradiation is reported in this study. SMPs exhibit stimuli-induced geometry changes and are being proposed for applications in numerous fields. We have previously reported a polyurethane SMP system that exhibits the complex processing capabilities of thermoplastic polymers and the mechanical robustness and tunability of thermomechanical properties that are often characteristic of thermoset materials. These previously reported polyurethanes suffer practically because the thermoplastic molecular weights needed to achieve target cross-link densities severely limit high-throughput thermoplastic processing and because thermally unstable radiation-sensitizing additives must be used to achieve high enough cross-link densities to enable desired tunable shape memory behavior. In this study, we demonstrate the ability to manipulate cross-link density in low-molecular weight aliphatic thermoplastic polyurethane SMPs (Mw as low as ~1.5 kDa) without radiation-sensitizing additives by incorporating specific structural motifs into the thermoplastic polymer side chains that we hypothesized would significantly enhance susceptibility to e-beam cross-linking. A custom diol monomer was first synthesized and then implemented in the synthesis of neat thermoplastic polyurethane SMPs that were irradiated at doses ranging from 1 to 500 kGy. Dynamic mechanical analysis (DMA) demonstrated rubbery moduli to be tailorable between 0.1 and 55 MPa, and both DMA and sol/gel analysis results provided fundamental insight into our hypothesized mechanism of electron beam cross-linking, which enables controllable bulk cross-linking to be achieved in highly processable, low-molecular weight thermoplastic shape memory polymers without sensitizing additives. PMID:25411511

Evaluation of imipenem for prophylaxis and therapy of Yersinia pestis delivered by aerosol in a mouse model of pneumonic plague.

PubMed

Heine, Henry S; Louie, Arnold; Adamovicz, Jeffrey J; Amemiya, Kei; Fast, Randy L; Miller, Lynda; Opal, Steven M; Palardy, John; Parejo, Nicolas A; Sörgel, Fritz; Kinzig-Schippers, Martina; Drusano, George L

2014-06-01

It has been previously shown that mice subjected to an aerosol exposure to Yersinia pestis and treated with β-lactam antibiotics after a delay of 42 h died at an accelerated rate compared to controls. It was hypothesized that endotoxin release in antibiotic-treated mice accounted for the accelerated death rate in the mice exposed to aerosol Y. pestis. Imipenem, a β-lactam antibiotic, binds to penicillin binding protein 2 with the highest affinity and produces rounded cells. The binding of imipenem causes cells to lyse quickly and thereby to release less free endotoxin. Two imipenem regimens producing fractions of time that the concentration of free, unbound drug was above the MIC (fT>MIC) of approximately 25% (6/24 h) and 40% (9.5/24 h) were evaluated. In the postexposure prophylaxis study, the 40% and 25% regimens produced 90% and 40% survivorship, respectively. In the 42-h treatment study, both regimens demonstrated a 40 to 50% survivorship at therapy cessation and some deaths thereafter, resulting in a 30% survivorship. As this was an improvement over the results with other β-lactams, a comparison of both endotoxin and cytokine levels in mice treated with imipenem and ceftazidime (a β-lactam previously demonstrated to accelerate death in mice during treatment) was performed and supported the original hypotheses; however, the levels observed in animals treated with ciprofloxacin (included as an unrelated antibiotic that is also bactericidal but should cause little lysis due to a different mode of action) were elevated and significantly (7-fold) higher than those with ceftazidime. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Evaluation of Imipenem for Prophylaxis and Therapy of Yersinia pestis Delivered by Aerosol in a Mouse Model of Pneumonic Plague

PubMed Central

Louie, Arnold; Adamovicz, Jeffrey J.; Amemiya, Kei; Fast, Randy L.; Miller, Lynda; Opal, Steven M.; Palardy, John; Parejo, Nicolas A.; Sörgel, Fritz; Kinzig-Schippers, Martina; Drusano, George L.

2014-01-01

It has been previously shown that mice subjected to an aerosol exposure to Yersinia pestis and treated with β-lactam antibiotics after a delay of 42 h died at an accelerated rate compared to controls. It was hypothesized that endotoxin release in antibiotic-treated mice accounted for the accelerated death rate in the mice exposed to aerosol Y. pestis. Imipenem, a β-lactam antibiotic, binds to penicillin binding protein 2 with the highest affinity and produces rounded cells. The binding of imipenem causes cells to lyse quickly and thereby to release less free endotoxin. Two imipenem regimens producing fractions of time that the concentration of free, unbound drug was above the MIC (fT>MIC) of approximately 25% (6/24 h) and 40% (9.5/24 h) were evaluated. In the postexposure prophylaxis study, the 40% and 25% regimens produced 90% and 40% survivorship, respectively. In the 42-h treatment study, both regimens demonstrated a 40 to 50% survivorship at therapy cessation and some deaths thereafter, resulting in a 30% survivorship. As this was an improvement over the results with other β-lactams, a comparison of both endotoxin and cytokine levels in mice treated with imipenem and ceftazidime (a β-lactam previously demonstrated to accelerate death in mice during treatment) was performed and supported the original hypotheses; however, the levels observed in animals treated with ciprofloxacin (included as an unrelated antibiotic that is also bactericidal but should cause little lysis due to a different mode of action) were elevated and significantly (7-fold) higher than those with ceftazidime. PMID:24687492

Associations Between United States Medical Licensing Examination (USMLE) and Internal Medicine In-Training Examination (IM-ITE) Scores

PubMed Central

Zeger, Scott L.; Kolars, Joseph C.

2008-01-01

Background Little is known about the associations of previous standardized examination scores with scores on subsequent standardized examinations used to assess medical knowledge in internal medicine residencies. Objective To examine associations of previous standardized test scores on subsequent standardized test scores. Design Retrospective cohort study. Participants One hundred ninety-five internal medicine residents. Methods Bivariate associations of United States Medical Licensing Examination (USMLE) Steps and Internal Medicine In-Training Examination (IM-ITE) scores were determined. Random effects analysis adjusting for repeated administrations of the IM-ITE and other variables known or hypothesized to affect IM-ITE score allowed for discrimination of associations of individual USMLE Step scores on IM-ITE scores. Results In bivariate associations, USMLE scores explained 17% to 27% of the variance in IME-ITE scores, and previous IM-ITE scores explained 66% of the variance in subsequent IM-ITE scores. Regression coefficients (95% CI) for adjusted associations of each USMLE Step with IM-ITE scores were USMLE-1 0.19 (0.12, 0.27), USMLE-2 0.23 (0.17, 0.30), and USMLE-3 0.19 (0.09, 0.29). Conclusions No single USMLE Step is more strongly associated with IM-ITE scores than the others. Because previous IM-ITE scores are strongly associated with subsequent IM-ITE scores, appropriate modeling, such as random effects methods, should be used to account for previous IM-ITE administrations in studies for which IM-ITE score is an outcome. PMID:18612735

Associations between United States Medical Licensing Examination (USMLE) and Internal Medicine In-Training Examination (IM-ITE) scores.

PubMed

McDonald, Furman S; Zeger, Scott L; Kolars, Joseph C

2008-07-01

Little is known about the associations of previous standardized examination scores with scores on subsequent standardized examinations used to assess medical knowledge in internal medicine residencies. To examine associations of previous standardized test scores on subsequent standardized test scores. Retrospective cohort study. One hundred ninety-five internal medicine residents. Bivariate associations of United States Medical Licensing Examination (USMLE) Steps and Internal Medicine In-Training Examination (IM-ITE) scores were determined. Random effects analysis adjusting for repeated administrations of the IM-ITE and other variables known or hypothesized to affect IM-ITE score allowed for discrimination of associations of individual USMLE Step scores on IM-ITE scores. In bivariate associations, USMLE scores explained 17% to 27% of the variance in IME-ITE scores, and previous IM-ITE scores explained 66% of the variance in subsequent IM-ITE scores. Regression coefficients (95% CI) for adjusted associations of each USMLE Step with IM-ITE scores were USMLE-1 0.19 (0.12, 0.27), USMLE-2 0.23 (0.17, 0.30), and USMLE-3 0.19 (0.09, 0.29). No single USMLE Step is more strongly associated with IM-ITE scores than the others. Because previous IM-ITE scores are strongly associated with subsequent IM-ITE scores, appropriate modeling, such as random effects methods, should be used to account for previous IM-ITE administrations in studies for which IM-ITE score is an outcome.

The six-minute walk test as a measure of postoperative recovery after colorectal resection: further examination of its measurement properties.

PubMed

Pecorelli, Nicolò; Fiore, Julio F; Gillis, Chelsia; Awasthi, Rashami; Mappin-Kasirer, Benjamin; Niculiseanu, Petru; Fried, Gerald M; Carli, Francesco; Feldman, Liane S

2016-06-01

Patients, clinicians and researchers seek an easy, reproducible and valid measure of postoperative recovery. The six-minute walk test (6MWT) is a low-cost measure of physical function, which is a relevant dimension of recovery. The aim of the present study was to contribute further evidence for the validity of the 6MWT as a measure of postoperative recovery after colorectal surgery. This study involved a sample of 174 patients enrolled in three previous randomized controlled trials. Construct validity was assessed by testing the hypotheses that the distance walked in 6 min (6MWD) at 4 weeks after surgery is greater (1) in younger versus older patients, (2) in patients with higher preoperative physical status versus lower, (3) after laparoscopic versus open surgery, (4) in patients without postoperative complications versus with postoperative complications; and that 6MWD (5) correlates cross-sectionally with self-reported physical activity as measured with a questionnaire (CHAMPS). Statistical analysis was performed using linear regression and Spearman's correlation. The COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist was used to guide the formulation of hypotheses and reporting of results. One hundred and fifty-one patients who completed the 6MWT at 4 weeks after surgery were included in the analysis. All hypotheses tested for construct validity were supported by the data. Older age, poorer physical status, open surgery and occurrence of postoperative complications were associated with clinically relevant reduction in 6MWD (>19 m). There was a moderate positive correlation between 6MWD and patient-reported physical activity (r = 0.46). This study contributes further evidence for the construct validity of the 6MWT as a measure of postoperative recovery after colorectal surgery. Results from this study support the use of the 6MWT as an outcome measure in studies evaluating interventions aimed to improve postoperative recovery.

Skeletal morphology of the forefoot in shrews (Mammalia: Soricidae) of the genus Cryptotis, as revealed by digital x-rays

USGS Publications Warehouse

Woodman, N.; Morgan, J.P.J.

2005-01-01

Variation in the forefoot skeleton of small-eared shrews (family Soricidae, genus Cryptotis) has been previously documented, but the paucity of available skeletons for most taxa makes assessment of the degrees of intraspecific and interspecific variation difficult. We used a digital X-ray system to extract images of the forefoot skeleton from 101 dried skins of eight taxa (seven species, including two subspecies of one species) of these shrews. Lengths and widths of each of the four bones of digit III were measured directly from the digital images, and we used these data to quantify variation within and among taxa. Analysis of the images and measurements showed that interspecific variation exceeds intraspecific variation. In fact, most taxa could be distinguished in multivariate and some bivariate plots. Our quantitative data helped us define a number of specific forefoot characters that we subsequently used to hypothesize evolutionary relationships among the taxa using the exhaustive search option in PAUP, a computer program for phylogenetic analysis. The resulting trees generally concur with previously published evolutionary hypotheses for small-eared shrews. Cryptotis meridensis, a taxon not previously examined in recent phylogenies, is rooted at the base of the branch leading to the C. mexicana group of species. The position of this species suggests that the mostly South American C. thomasi group shares an early ancestor with the C. mexicana group.

Child loss and psychosis onset: evidence for traumatic experience as an etiological factor in psychosis.

PubMed

Devylder, Jordan E; Wang, Julia S-H; Oh, Hans Y; Lukens, Ellen P

2013-01-30

Previous research suggests that trauma may contribute to psychosis onset. In this study, we examine the effect of parental loss of a child on the onset of psychotic experience using data from the National Comorbidity Survey Replication, hypothesizing that child loss will precede the onset of psychosis and will be associated with a later age of onset. We likewise tested this association for six other psychiatric conditions to demonstrate specificity for psychosis. Individuals with a psychotic disorder who had lost a child had a significantly later age of onset, particularly in males, even when controlling for demographic variables and co-occurring substance abuse and psychiatric disorders. Psychosis onset frequently occurred within a year of child loss. No associations were found between child loss and onset of other psychiatric conditions, supporting specificity of the effect on psychosis. The presented findings implicate child loss as an etiological factor in the onset of psychosis, providing converging evidence with previous studies demonstrating associations between more widely studied trauma exposures (abuse, neglect, and assault) and psychosis. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Classroom-Based Science Research at the Introductory Level: Changes in Career Choices and Attitude

PubMed Central

Harrison, Melinda; Dunbar, David; Ratmansky, Lisa; Lopatto, David

2011-01-01

Our study, focused on classroom-based research at the introductory level and using the Phage Genomics course as the model, shows evidence that first-year students doing research learn the process of science as well as how scientists practice science. A preliminary but notable outcome of our work, which is based on a small sample, is the change in student interest in considering different career choices such as graduate education and science in general. This is particularly notable, as previous research has described research internships as clarifying or confirming rather than changing undergraduates’ decisions to pursue graduate education. We hypothesize that our results differ from previous studies of the impact of engaging in research because the students in our study are still in the early stages of their undergraduate careers. Our work builds upon the classroom-based research movement and should be viewed as encouraging to the Vision and Change in Undergraduate Biology Education movement advocated by the American Association for the Advancement of Science, the National Science Foundation, and other undergraduate education stakeholders. PMID:21885824

Boldness, Aggression, and Shoaling Assays for Zebrafish Behavioral Syndromes.

PubMed

Way, Gregory P; Southwell, Maura; McRobert, Scott P

2016-08-29

A behavioral syndrome exists when specific behaviors interact under different contexts. Zebrafish have been test subjects in recent studies and it is important to standardize protocols to ensure proper analyses and interpretations. In our previous studies, we have measured boldness by monitoring a series of behaviors (time near surface, latency in transitions, number of transitions, and darts) in a 1.5 L trapezoidal tank. Likewise, we quantified aggression by observing bites, lateral displays, darts, and time near an inclined mirror in a rectangular 19 L tank. By dividing a 76 L tank into thirds, we also examined shoaling preferences. The shoaling assay is a highly customizable assay and can be tailored for specific hypotheses. However, protocols for this assay also must be standardized, yet flexible enough for customization. In previous studies, end chambers were either empty, contained 5 or 10 zebrafish, or 5 pearl danios (D. albolineatus). In the following manuscript, we present a detailed protocol and representative data that accompany successful applications of the protocol, which will allow for replication of behavioral syndrome experiments.

Classroom-based science research at the introductory level: changes in career choices and attitude.

PubMed

Harrison, Melinda; Dunbar, David; Ratmansky, Lisa; Boyd, Kimberly; Lopatto, David

2011-01-01

Our study, focused on classroom-based research at the introductory level and using the Phage Genomics course as the model, shows evidence that first-year students doing research learn the process of science as well as how scientists practice science. A preliminary but notable outcome of our work, which is based on a small sample, is the change in student interest in considering different career choices such as graduate education and science in general. This is particularly notable, as previous research has described research internships as clarifying or confirming rather than changing undergraduates' decisions to pursue graduate education. We hypothesize that our results differ from previous studies of the impact of engaging in research because the students in our study are still in the early stages of their undergraduate careers. Our work builds upon the classroom-based research movement and should be viewed as encouraging to the Vision and Change in Undergraduate Biology Education movement advocated by the American Association for the Advancement of Science, the National Science Foundation, and other undergraduate education stakeholders.

Prefrontal Cortical GABA Levels in Panic Disorder Determined by Proton Magnetic Resonance Spectroscopy

PubMed Central

Hasler, Gregor; van der Veen, Jan Willem; Geraci, Marilla; Shen, Jun; Pine, Daniel; Drevets, Wayne C.

2009-01-01

Background Panic disorder (PD) is hypothesized to be associated with altered function of the major inhibitory neurotransmitter, gamma-amino butyric acid (GABA). Previous proton magnetic resonance spectroscopy (MRS) studies found lower GABA concentrations in the occipital cortex of subjects with PD relative to healthy controls. The current study is the first MRS study to compare GABA concentrations between unmedicated PD subjects and controls in the prefrontal cortex (PFC). Methods Unmedicated subjects with PD (n=17) and age- and sex-matched healthy controls (n=17) were scanned on a 3 Tesla scanner using a transmit-receive head coil that provided a sufficiently homogenous radiofrequency field to obtain spectroscopic measurements in the dorsomedial/dorsal anterolateral and ventromedial areas of the PFC. Results The prefrontal cortical GABA concentrations did not differ significantly between PD subjects and controls. There also was no statistically significant difference in Glx, choline or N-acetyl-aspartate concentrations. Conclusions The previously reported finding of reduced GABA concentrations in the occipital cortex of PD subjects does not appear to extend to the PFC. PMID:18692172

Individual Differences in Sequence Learning Ability and Second Language Acquisition in Early Childhood and Adulthood

ERIC Educational Resources Information Center

Granena, Gisela

2013-01-01

Language aptitude has been hypothesized as a factor that can compensate for postcritical period effects in language learning capacity. However, previous research has primarily focused on instructed contexts and rarely on acquisition-rich learning environments where there is a potential for massive amounts of input. In addition, the studies…

Jim and Dave: A Dialogue.

ERIC Educational Resources Information Center

Doud, Robert E.

This is a fictional dialogue intended to honor Jim Kingman and David Leary, both professors of history who retired after long careers at Pasadena City College in California (PCC). The dialogue hypothesizes the observations of both men as they look on the honorary gold plates of previous retirees that decorate the wall of a PCC public dining hall.…

A Comparison of Activities and Behaviors in Coeducational and Non-Coeducational Residence Halls.

ERIC Educational Resources Information Center

Maryland Univ., College Park.

This report reviews the objectives for coed housing, relates previous findings, and examines several hypotheses: (1) that coed units will have more activities and programs; (2) that the activities will be more widely varied; (3) that coed residents report more contact with faculty, more interaction with the opposite sex, more academically oriented…

Prospective Associations of Co-Rumination with Friendship and Emotional Adjustment: Considering the Socioemotional Trade-Offs of Co-Rumination

ERIC Educational Resources Information Center

Rose, Amanda J.; Carlson, Wendy; Waller, Erika M.

2007-01-01

Co-ruminating, or excessively discussing problems, with friends is proposed to have adjustment tradeoffs. Co-rumination is hypothesized to contribute both to positive friendship adjustment and to problematic emotional adjustment. Previous single-assessment research was consistent with this hypothesis, but whether co-rumination is an antecedent…

Evidence for Kind Representations in the Absence of Language: Experiments with Rhesus Monkeys ("Macaca Mulatta")

ERIC Educational Resources Information Center

Phillips, Webb; Santos, Laurie R.

2007-01-01

How do we come to recognize and represent different kinds of objects in the world? Some developmental psychologists have hypothesized that learning language plays a crucial role in this capacity. If this hypothesis were correct, then non-linguistic animals should lack the capacity to represent objects as kinds. Previous research with rhesus…

The Effect of Observational Learning on Students' Performance, Processes, and Motivation in Two Creative Domains

ERIC Educational Resources Information Center

Groenendijk, Talita; Janssen, Tanja; Rijlaarsdam, Gert; van den Bergh, Huub

2013-01-01

Background. Previous research has shown that observation can be effective for learning in various domains, for example, argumentative writing and mathematics. The question in this paper is whether observational learning can also be beneficial when learning to perform creative tasks in visual and verbal arts. Aims. We hypothesized that observation…

Threshold Switchable Particles (TSP) to Control Internal Hemorrhage

DTIC Science & Technology

2014-12-01

be markers of disease. Nudt2 (Apah1), for example, is an Ap4A hydrolase that, when overexpressed in breast cancer, correlates with poor prognosis.26...In addition to processing Ap4A , Nudt2 can hydrolyze long-chain NpnNs such as Ap6A. We hypothesized that this nudix enzyme, though previously not

The Relentless Search for Effects of Divorce: Forging New Trails or Tumbling down the Beaten Path?

ERIC Educational Resources Information Center

Demo, David H.

1993-01-01

Responds to previous article by Amato on children's adjustment to divorce. Cites number of serious limitations including problems in language and logic of hypothesis-testing, in derivation of hypotheses, and in interpretation and assessment of accumulated evidence. Finds Amato's basic premise--that children of divorce suffer lifelong adjustment…

Simulated nitrogen deposition affects community structure of arbuscular mycorrhizal fungi in northern hardwood forests

Treesearch

Linda T.A. Van Diepen; Erik Lilleskov; Kurt S. Pregitzer

2011-01-01

Our previous investigation found elevated nitrogen deposition caused declines in abundance of arbuscular mycorrhizal fungi (AMF) associated with forest trees, but little is known about how nitrogen affects the AMF community composition and structure within forest ecosystems. We hypothesized that N deposition would lead to significant changes in the AMF community...

Associating Neural Alterations and Genotype in Autism and Fragile X Syndrome: Incorporating Perceptual Phenotypes in Causal Modeling

ERIC Educational Resources Information Center

Bertone, Armando; Hanck, Julie; Kogan, Cary; Chaudhuri, Avi; Cornish, Kim

2010-01-01

We have previously described (see companion paper, this issue) the utility of using perceptual signatures for defining and dissociating condition-specific neural functioning underlying early visual processes in autism and FXS. These perceptually-driven hypotheses are based on differential performance evidenced only at the earliest stages of visual…

The potential value of sibling controls compared with population controls for association studies of lifestyle-related risk factors: an example from the Breast Cancer Family Registry.

PubMed

Milne, Roger L; John, Esther M; Knight, Julia A; Dite, Gillian S; Southey, Melissa C; Giles, Graham G; Apicella, Carmel; West, Dee W; Andrulis, Irene L; Whittemore, Alice S; Hopper, John L

2011-10-01

A previous Australian population-based breast cancer case-control study found indirect evidence that control participation, although high, was not random. We hypothesized that unaffected sisters may provide a more appropriate comparison group than unrelated population controls. Three population-based case-control-family studies of breast cancer in women of white European origin were carried out by the Australian, Ontario and Northern California sites of the Breast Cancer Family Registry. We compared risk factors between 3643 cases, 2444 of their unaffected sisters and 2877 population controls and conducted separate case-control analyses based on population and sister controls using unconditional multivariable logistic regression. Compared with sister controls, population controls were more highly educated, had an earlier age at menarche, fewer births, their first birth at a later age and their last birth more recently. The established breast cancer associations detected using sister controls, but not detected using population controls, were decreasing risk with each of later age at menarche, more births, younger age at first birth and greater time since last birth. Since participation of population controls might be unintentionally related to some risk factors, we hypothesize that sister controls could provide more valid relative risk estimates and be recruited at lower cost. Given declining study participation by population controls, this contention is highly relevant to epidemiologic research.

A comparative analysis of experimental selection on the stickleback pelvis.

PubMed

Miller, S E; Barrueto, M; Schluter, D

2017-06-01

Mechanisms of natural selection can be identified using experimental approaches. However, such experiments often yield nonsignificant effects and imprecise estimates of selection due to low power and small sample sizes. Combining results from multiple experimental studies might produce an aggregate estimate of selection that is more revealing than individual studies. For example, bony pelvic armour varies conspicuously among stickleback populations, and predation by vertebrate and insect predators has been hypothesized to be the main driver of this variation. Yet experimental selection studies testing these hypotheses frequently fail to find a significant effect. We experimentally manipulated length of threespine stickleback (Gasterosteus aculeatus) pelvic spines in a mesocosm experiment to test whether prickly sculpin (Cottus asper), an intraguild predator of stickleback, favours longer spines. The probability of survival was greater for stickleback with unclipped pelvic spines, but this effect was noisy and not significant. We used meta-analysis to combine the results of our mesocosm experiment with previously published experimental studies of selection on pelvic armour. We found evidence that fish predation indeed favours increased pelvic armour, with a moderate effect size. The same approach found little evidence that insect predation favours reduced pelvic armour. The causes of reduced pelvic armour in many stickleback populations remain uncertain. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

A reassessment of state-level covariates of militia groups.

PubMed

Freilich, Joshua D; Pridemore, William Alex

2005-01-01

This study investigated state-level variation in the number of right-wing militia groups. We built on prior quantitative examinations by more carefully operationalizing theoretical concepts and testing alternative hypotheses offered to account for the etiology of social movements generally and of militias specifically. Using negative binomial regression, we found that, consistent with previous research, states with higher levels of farm job loss had more militia groups. However, in contrast to prior studies, we did not find gun culture, hospitable political climate, female empowerment, or general economic deprivation to be associated with the number of militia groups. We also found no relationship between the number of militia groups and levels of fundamentalist religious culture and minority empowerment. Our study was the first to test the effects of social disorganization on the number of militias in a state, and we found the two to be positively and significantly associated. We situate our results in the theoretical and empirical literature and outline two challenges for future research. First, scholars must operationalize variables carefully since different measures of the same theoretical concept may result in diverging conclusions. Second, since one major factor (i.e., social disorganization) found in this study to be associated with the number of militia groups in a state was examined here for the first time, it is important for researchers to continue to investigate new hypotheses.

Theory of mind deficit in bipolar disorder: is it related to a previous history of psychotic symptoms?

PubMed

Lahera, Guillermo; Montes, José Manuel; Benito, Adolfo; Valdivia, María; Medina, Elena; Mirapeix, Isabel; Sáiz-Ruiz, Jerónimo

2008-12-15

It has been hypothesized that a Theory of Mind (ToM) deficit could be a vulnerability marker for psychosis. Recent studies, however, have shown ToM deficits in affective relapses of bipolar disorder as well as in the euthymic phase. This study analyzes the relationship between ToM and a previous history of psychotic symptoms in bipolar disorder. ToM, sustained attention and executive functions were analyzed in 75 bipolar euthymic patients with three or more previous relapses (42 of them had a history of psychotic symptoms and 33 did not) and 48 healthy subjects. ToM was assessed with the Advanced Test by Happé. ToM performance was similar in bipolar patients with or without a history of psychotic symptoms, and in both cases it was significantly reduced as compared with the healthy control group. Similarly, both bipolar groups showed impaired sustained attention and executive functions. This general cognitive deficit partially explains the differences obtained in ToM. The ToM instrument used shows low sensitivity for assessing ToM in bipolar patients and it could partially reflect general cognitive functioning rather than a specific deficit in psychosis. ToM deficit is not a trait marker for psychosis, given that it is present in bipolar disorder regardless of a previous history of psychotic symptoms.

The role of auditory feedback in music-supported stroke rehabilitation: A single-blinded randomised controlled intervention.

PubMed

van Vugt, F T; Kafczyk, T; Kuhn, W; Rollnik, J D; Tillmann, B; Altenmüller, E

2016-01-01

Learning to play musical instruments such as piano was previously shown to benefit post-stroke motor rehabilitation. Previous work hypothesised that the mechanism of this rehabilitation is that patients use auditory feedback to correct their movements and therefore show motor learning. We tested this hypothesis by manipulating the auditory feedback timing in a way that should disrupt such error-based learning. We contrasted a patient group undergoing music-supported therapy on a piano that emits sounds immediately (as in previous studies) with a group whose sounds are presented after a jittered delay. The delay was not noticeable to patients. Thirty-four patients in early stroke rehabilitation with moderate motor impairment and no previous musical background learned to play the piano using simple finger exercises and familiar children's songs. Rehabilitation outcome was not impaired in the jitter group relative to the normal group. Conversely, some clinical tests suggests the jitter group outperformed the normal group. Auditory feedback-based motor learning is not the beneficial mechanism of music-supported therapy. Immediate auditory feedback therapy may be suboptimal. Jittered delay may increase efficacy of the proposed therapy and allow patients to fully benefit from motivational factors of music training. Our study shows a novel way to test hypotheses concerning music training in a single-blinded way, which is an important improvement over existing unblinded tests of music interventions.

Predicting the math/science career goals of low-income prospective first-generation college students.

PubMed

Garriott, Patton O; Flores, Lisa Y; Martens, Matthew P

2013-04-01

The present study used social cognitive career theory (SCCT; Lent, Brown, & Hackett, 1994) to predict the math/science goal intentions of a sample of low-income prospective first-generation college students (N = 305). Structural equation modeling was used to test a model depicting relationships between contextual (i.e., social class, learning experiences, proximal supports and barriers) and person-cognitive (i.e., self-efficacy, outcome expectations, interests, goals) variables as hypothesized in SCCT and based on previous literature on low-income first-generation college students. Results indicated that the hypothesized model provided the best representation of the data. All paths in the model were statistically significant, with the exceptions of paths from self-efficacy to goals, outcome expectations to interests, and perceived barriers to self-efficacy. Bootstrapping procedures revealed that the relationships between social class, self-efficacy, and outcome expectations were mediated through learning experiences. Furthermore, the relationship between social supports and goals was mediated by self-efficacy and interests and the relationships between self-efficacy, outcome expectations, and goals were mediated by interests. Contrary to hypotheses, the relationship between barriers and goals was not mediated by self-efficacy and interests. The hypothesis that proximal contextual supports and barriers would moderate the relationship between interests and goals was not supported. The final model explained 66% and 55% of the variance in math/science interests and goals, respectively. Implications for future research and practice are discussed.

The Phenomenology of the Diagnostic Process: A Primary Care-Based Survey.

PubMed

Donner-Banzhoff, Norbert; Seidel, Judith; Sikeler, Anna Maria; Bösner, Stefan; Vogelmeier, Maria; Westram, Anja; Feufel, Markus; Gaissmaier, Wolfgang; Wegwarth, Odette; Gigerenzer, Gerd

2017-01-01

While dichotomous tasks and related cognitive strategies have been extensively researched in cognitive psychology, little is known about how primary care practitioners (general practitioners [GPs]) approach ill-defined or polychotomous tasks and how valid or useful their strategies are. To investigate cognitive strategies used by GPs for making a diagnosis. In a cross-sectional study, we videotaped 282 consultations, irrespective of presenting complaint or final diagnosis. Reflective interviews were performed with GPs after each consultation. Recordings of consultations and GP interviews were transcribed verbatim and analyzed using a coding system that was based on published literature and systematically checked for reliability. In total, 134 consultations included 163 diagnostic episodes. Inductive foraging (i.e., the initial, patient-guided search) could be identified in 91% of consultations. It contributed an average 31% of cues obtained by the GP in 1 consultation. Triggered routines and descriptive questions occurred in 38% and 84% of consultations, respectively. GPs resorted to hypothesis testing, the hallmark of the hypothetico-deductive method, in only 39% of consultations. Video recordings and interviews presumably interfered with GPs' behavior and accounts. GPs might have pursued more hypotheses and collected more information than usual. The testing of specific disease hypotheses seems to play a lesser role than previously thought. Our data from real consultations suggest that GPs organize their search for information in a skillfully adapted way. Inductive foraging, triggered routines, descriptive questions, and hypotheses testing are essential building blocks to make a diagnosis in the generalist setting. © The Author(s) 2016.

Performance of polygenic scores for predicting phobic anxiety.

PubMed

Walter, Stefan; Glymour, M Maria; Koenen, Karestan; Liang, Liming; Tchetgen Tchetgen, Eric J; Cornelis, Marilyn; Chang, Shun-Chiao; Rimm, Eric; Kawachi, Ichiro; Kubzansky, Laura D

2013-01-01

Anxiety disorders are common, with a lifetime prevalence of 20% in the U.S., and are responsible for substantial burdens of disability, missed work days and health care utilization. To date, no causal genetic variants have been identified for anxiety, anxiety disorders, or related traits. To investigate whether a phobic anxiety symptom score was associated with 3 alternative polygenic risk scores, derived from external genome-wide association studies of anxiety, an internally estimated agnostic polygenic score, or previously identified candidate genes. Longitudinal follow-up study. Using linear and logistic regression we investigated whether phobic anxiety was associated with polygenic risk scores derived from internal, leave-one out genome-wide association studies, from 31 candidate genes, and from out-of-sample genome-wide association weights previously shown to predict depression and anxiety in another cohort. Study participants (n = 11,127) were individuals from the Nurses' Health Study and Health Professionals Follow-up Study. Anxiety symptoms were assessed via the 8-item phobic anxiety scale of the Crown Crisp Index at two time points, from which a continuous phenotype score was derived. We found no genome-wide significant associations with phobic anxiety. Phobic anxiety was also not associated with a polygenic risk score derived from the genome-wide association study beta weights using liberal p-value thresholds; with a previously published genome-wide polygenic score; or with a candidate gene risk score based on 31 genes previously hypothesized to predict anxiety. There is a substantial gap between twin-study heritability estimates of anxiety disorders ranging between 20-40% and heritability explained by genome-wide association results. New approaches such as improved genome imputations, application of gene expression and biological pathways information, and incorporating social or environmental modifiers of genetic risks may be necessary to identify significant genetic predictors of anxiety.

The theory of planned behavior, materialism, and aggressive driving.

PubMed

Efrat, Kalanit; Shoham, Aviv

2013-10-01

Aggressive driving is a growing problem worldwide. Previous research has provided us with some insights into the characteristics of drivers prone to aggressiveness on the road and into the external conditions triggering such behavior. Little is known, however, about the personality traits of aggressive drivers. The present study proposes planned behavior and materialism as predictors of aggressive driving behavior. Data was gathered using a questionnaire-based survey of 220 individuals from twelve large industrial organizations in Israel. Our hypotheses were tested using structural equation modeling. Our results indicate that while planned behavior is a good predictor of the intention to behave aggressively, it has no impact on the tendency to behave aggressively. Materialism, however, was found to be a significant indicator of aggressive driving behavior. Our study is based on a self-reported survey, therefore might suffer from several issues concerning the willingness to answer truthfully. Furthermore, the sampling group might be seen as somewhat biased due to the relatively high income/education levels of the respondents. While both issues, aggressive driving and the theory of planned behavior, have been studied previously, the linkage between the two as well as the ability of materialism to predict aggressive behavior received little attention previously. The present study encompasses these constructs providing new insights into the linkage between them. Copyright © 2013 Elsevier Ltd. All rights reserved.

Effects of weak electromagnetic fields on Escherichia coli and Staphylococcus aureus

NASA Astrophysics Data System (ADS)

Smith, Derek A.

Previous studies of electromagnetic field effects on bacteria are examined, and new experimental procedures and their results are discussed. Experimental samples of Escherichia coli and Staphylococcus aureus were prepared in different conditions, and measurements of optical density were used to track growth rates after removing the samples from their associated experimental environments. Experimental environments varied in magnetic field intensities and frequencies, including a control environment of minimal field intensity. Plots of experimental data sets and their associated averages are used to visualize the experimental outcomes, and differences in growth patterns are evaluated. Results are then used to hypothesize the mechanisms and consequences of the potentially observed field effects.

Thinking of you: nonconscious pursuit of interpersonal goals associated with relationship partners.

PubMed

Fitzsimons, Gráinne M; Bargh, John A

2003-01-01

The mere psychological presence of relationship partners was hypothesized to trigger interpersonal goals that are then pursued nonconsciously. Qualitative data suggested that people tend to pursue different interpersonal goals within different types of relationships (e.g., mother, best friend, coworker). In several studies, priming participants' relationship representations produced goal-directed behavior (achievement, helping, understanding) in line with the previously assessed goal content of those representations. These findings support the hypothesis that interpersonal goals are component features of relationship representations and that mere activation of those representations, even in the partner's physical absence, causes the goals to become active and to guide behavior nonconsciously within the current situation.

Managing HIV at the workplace: An empirical study of HIV and HR managers in Singapore.

PubMed

Lim, Vivien K G

2003-10-01

Drawing from previous research on individual differences, AIDS, and concerns for face, the author developed and tested a model examining the predictors (knowledge of AIDS transmission, level of homophobia, and concern for face) of AIDS fear and its organizational outcomes (perceived organizational consequences of hiring people living with HIV and attitudes toward disclosure of HIV-related information at the workplace). Data were collected using mail survey. Structural equation modeling was used to examine the relationships among these variables for 160 human resource managers. All of the hypothesized relationships were empirically supported. Implications of the research findings for human resource practices are discussed. 2003 APA

Analysis of PubMed User Sessions Using a Full-Day PubMed Query Log: A Comparison of Experienced and Nonexperienced PubMed Users

PubMed Central

2015-01-01

Background PubMed is the largest biomedical bibliographic information source on the Internet. PubMed has been considered one of the most important and reliable sources of up-to-date health care evidence. Previous studies examined the effects of domain expertise/knowledge on search performance using PubMed. However, very little is known about PubMed users’ knowledge of information retrieval (IR) functions and their usage in query formulation. Objective The purpose of this study was to shed light on how experienced/nonexperienced PubMed users perform their search queries by analyzing a full-day query log. Our hypotheses were that (1) experienced PubMed users who use system functions quickly retrieve relevant documents and (2) nonexperienced PubMed users who do not use them have longer search sessions than experienced users. Methods To test these hypotheses, we analyzed PubMed query log data containing nearly 3 million queries. User sessions were divided into two categories: experienced and nonexperienced. We compared experienced and nonexperienced users per number of sessions, and experienced and nonexperienced user sessions per session length, with a focus on how fast they completed their sessions. Results To test our hypotheses, we measured how successful information retrieval was (at retrieving relevant documents), represented as the decrease rates of experienced and nonexperienced users from a session length of 1 to 2, 3, 4, and 5. The decrease rate (from a session length of 1 to 2) of the experienced users was significantly larger than that of the nonexperienced groups. Conclusions Experienced PubMed users retrieve relevant documents more quickly than nonexperienced PubMed users in terms of session length. PMID:26139516

Validating Variance Similarity Functions in the Entrainment Zone

NASA Astrophysics Data System (ADS)

Osman, M.; Turner, D. D.; Heus, T.; Newsom, R. K.

2017-12-01

In previous work, the water vapor variance in the entrainment zone was proposed to be proportional to the convective velocity scale, gradient water vapor mixing ratio and the Brunt-Vaisala frequency in the interfacial layer, while the variance of the vertical wind at in the entrainment zone was defined in terms of the convective velocity scale. The variances in the entrainment zone have been hypothesized to depend on two distinct functions, which also depend on the Richardson number. To the best of our knowledge, these hypotheses have never been tested observationally. Simultaneous measurements of the Eddy correlation surface flux, wind shear profiles from wind profilers, and variance profile measurements of vertical motions and water vapor by Doppler and Raman lidars, respectively, provide a unique opportunity to thoroughly examine the functions used in defining the variances and validate them. These observations were made over the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site. We have identified about 30 cases from 2016 during which the convective boundary layer (CBL) is quasi-stationary and well mixed for at least 2 hours. The vertical profiles of turbulent fluctuations of the vertical wind and water vapor have been derived using an auto covariance technique to separate out the instrument random error to a set of 2-h period time series. The error analysis of the lidars observations demonstrates that the lidars are capable of resolving the vertical structure of turbulence around the entrainment zone. Therefore, utilizing this unique combination of observations, this study focuses on extensively testing the hypotheses that the second-order moments are indeed proportional to the functions which also depend on Richardson number. The coefficients that are used in defining the functions will also be determined observationally and compared against with the values suggested by Large eddy simulation (LES) studies.

Salivary testosterone levels in men at a U.S. sex club.

PubMed

Escasa, Michelle J; Casey, Jacqueline F; Gray, Peter B

2011-10-01

Vertebrate males commonly experience elevations in testosterone levels in response to sexual stimuli, such as presentation of a novel mating partner. Some previous human studies have shown that watching erotic movies increases testosterone levels in males although studies measuring testosterone changes during actual sexual intercourse or masturbation have yielded mixed results. Small sample sizes, "unnatural" lab-based settings, and invasive techniques may help account for mixed human findings. Here, we investigated salivary testosterone levels in men watching (n = 26) versus participating (n = 18) in sexual activity at a large U.S. sex club. The present study entailed minimally invasive sample collection (measuring testosterone in saliva), a naturalistic setting, and a larger number of subjects than previous work to test three hypotheses related to men's testosterone responses to sexual stimuli. Subjects averaged 40 years of age and participated between 11:00 pm and 2:10 am. Consistent with expectations, results revealed that testosterone levels increased 36% among men during a visit to the sex club, with the magnitude of testosterone change significantly greater among participants (72%) compared with observers (11%). Contrary to expectation, men's testosterone changes were unrelated to their age. These findings were generally consistent with vertebrate studies indicating elevated male testosterone in response to sexual stimuli, but also point out the importance of study context since participation in sexual behavior had a stronger effect on testosterone increases in this study but unlike some previous human lab-based studies.

Exploring relation types for literature-based discovery.

PubMed

Preiss, Judita; Stevenson, Mark; Gaizauskas, Robert

2015-09-01

Literature-based discovery (LBD) aims to identify "hidden knowledge" in the medical literature by: (1) analyzing documents to identify pairs of explicitly related concepts (terms), then (2) hypothesizing novel relations between pairs of unrelated concepts that are implicitly related via a shared concept to which both are explicitly related. Many LBD approaches use simple techniques to identify semantically weak relations between concepts, for example, document co-occurrence. These generate huge numbers of hypotheses, difficult for humans to assess. More complex techniques rely on linguistic analysis, for example, shallow parsing, to identify semantically stronger relations. Such approaches generate fewer hypotheses, but may miss hidden knowledge. The authors investigate this trade-off in detail, comparing techniques for identifying related concepts to discover which are most suitable for LBD. A generic LBD system that can utilize a range of relation types was developed. Experiments were carried out comparing a number of techniques for identifying relations. Two approaches were used for evaluation: replication of existing discoveries and the "time slicing" approach.(1) RESULTS: Previous LBD discoveries could be replicated using relations based either on document co-occurrence or linguistic analysis. Using relations based on linguistic analysis generated many fewer hypotheses, but a significantly greater proportion of them were candidates for hidden knowledge. The use of linguistic analysis-based relations improves accuracy of LBD without overly damaging coverage. LBD systems often generate huge numbers of hypotheses, which are infeasible to manually review. Improving their accuracy has the potential to make these systems significantly more usable. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association.

Investigating middle-atmospheric gravity waves associated with a sprite-producing mesoscale convective event

NASA Astrophysics Data System (ADS)

Vollmer, D. R.; McHarg, M. G.; Harley, J.; Haaland, R. K.; Stenbaek-Nielsen, H.

2016-12-01

On 23 July 2014, a mesoscale convective event over western Nebraska produced a large number of sprites. One frame per second images obtained from a low-noise Andor Scientific CMOS camera showed regularly-spaced horizontal striations in the airglow both before and during several of the sprite events, suggesting the presence of vertically-propagating gravity waves in the middle atmosphere. Previous work hypothesized that the gravity waves were produced by the thunderstorm itself. We compare our observations with previous work, and present numerical simulations conducted to determine source, structure, and propagation of atmospheric gravity waves.

Predicting children's sunscreen use: application of the theories of reasoned action and planned behavior.

PubMed

Martin, S C; Jacobsen, P B; Lucas, D J; Branch, K A; Ferron, J M

1999-07-01

Skin cancer remains the most common form of cancer in the United States despite the fact that most cases can be prevented by limiting sun exposure. Childhood and adolescence are periods of life during which prolonged sun exposure is particularly common. Accordingly, promoting sun-protective behaviors during these formative years can be of critical importance in preventing skin cancer. The present study applied the theories of reasoned action and planned behavior to the understanding of children's sunscreen use. Based on these theories, it was hypothesized that attitudes, subjective norms, and perceived behavioral control would be related to intentions to use sunscreen, which, in turn, would be related to actual sunscreen use. Questionnaires measuring sun-related attitudes, beliefs, perceived control, and intentions were administered to 199 fourth graders (ages 9 to 13, mean = 10.3) attending public schools in Florida. Self-report measures of sun-related behavior were administered to the same subjects 1 month later. Results of correlational analyses were consistent with study hypotheses. Higher rates of sunscreen use at follow-up were predicted by stronger intentions to use sunscreen assessed 1 month previously. In addition, stronger intentions to use sunscreen were found to be related to more favorable attitudes toward sunscreen use, stronger beliefs that peers and parents favored sunscreen use, and greater perceptions of personal control in using sunscreen. Path and multiple regression analyses identified direct and indirect relationships among study variables that partially confirmed those predicted by the theories and provided support for the use of an expanded model that included perceived behavioral control. The present study confirmed hypotheses derived from the theories of reasoned action and planned behavior regarding the relation of attitudes, subjective norms, and perceived behavioral control to sunscreen use among fourth graders. In addition to their theoretical significance, these findings suggest ways to intervene at the individual, classroom, and family levels to promote greater sunscreen use in this age group. Copyright 1999 American Health Foundation and Academic Press.

Specifying content and mechanisms of change in interventions to change professionals' practice: an illustration from the Good Goals study in occupational therapy.

PubMed

Kolehmainen, Niina; Francis, Jill J

2012-10-18

It is widely agreed that interventions to change professionals' practice need to be clearly specified. This involves (1) selecting and defining the intervention techniques, (2) operationalising the techniques and deciding their delivery, and (3) formulating hypotheses about the mechanisms through which the techniques are thought to result in change. Descriptions of methods to achieve these objectives are limited. This paper reports methods and illustrates outputs from a study to meet these objectives, specifically from the Good Goals study to improve occupational therapists' caseload management practice. (1) Behaviour change techniques were identified and selected from an existing matrix that maps techniques to determinants. An existing coding manual was used to define the techniques. (2) A team of occupational therapists generated context-relevant, acceptable modes of delivery for the techniques; these data were compared and contrasted with previously collected data, literature on caseload management, and the aims of the intervention. (3) Hypotheses about the mechanisms of change were formulated by drawing on the matrix and on theories of behaviour change. (1) Eight behaviour change techniques were selected: goal specified; self-monitoring; contract; graded tasks; increasing skills (problem solving, decision making, goal setting); coping skills; rehearsal of relevant skills; social processes of encouragement, support, and pressure; demonstration by others; and feedback. (2) A range of modes of delivery were generated (e.g., graded tasks' consisting of series of clinical cases and situations that become increasingly difficult). Conditions for acceptable delivery were identified (e.g., 'self-monitoring' was acceptable only if delivered at team level). The modes of delivery were specified as face-to-face training, task sheets, group tasks, DVDs, and team-based weekly meetings. (3) The eight techniques were hypothesized to target caseload management practice through eleven mediating variables. Three domains were hypothesized to be most likely to change: beliefs about capabilities, motivation and goals, and behavioural regulation. The project provides an exemplar of a systematic and reportable development of a quality-improvement intervention, with its methods likely to be applicable to other projects. A subsequent study of the intervention has provided early indication that use of systematic methods to specify interventions may help to maximize acceptability and effectiveness.

Depletion, moral identity, and unethical behavior: Why people behave unethically after self-control exertion.

PubMed

Wang, Yan; Wang, Guosen; Chen, Qiuju; Li, Lin

2017-11-01

Self-control enables people to resist short-term temptations in the service of long-term goals. Previous exertion of self-control leads to a state of ego depletion. Three studies demonstrated that ego depletion leads to a high level of unethical behavior. These studies also hypothesized and confirmed that depleted individuals behave unethically because of low moral identity. Study 1 found that depleted participants were more likely to over-report their performance than non-depleted participants. Study 2 revealed that depletion reduced people's moral identity, which in turn increased their propensity to engage in unethical behavior. Study 3 proved that priming moral identity eliminated the effect of depletion on cheating. Findings suggest that reduced moral identity accounts for the effect of self-control depletion on unethical behavior. Copyright © 2017 Elsevier Inc. All rights reserved.

No effect of trait anxiety on differential fear conditioning or fear generalization.

PubMed

Torrents-Rodas, David; Fullana, Miquel A; Bonillo, Albert; Caseras, Xavier; Andión, Oscar; Torrubia, Rafael

2013-02-01

Previous studies have shown that individuals with anxiety disorders exhibit deficits in fear inhibition and excessive generalization of fear, but little data exist on individuals at risk from these disorders. The present study examined the role of trait anxiety in the acquisition and generalization of fear in 126 healthy participants selected on the basis of their trait-anxiety scores. Measures of conditioning included fear-potentiated startle, skin conductance response and online risk ratings for the unconditioned stimulus. Contrary to our hypotheses, trait anxiety did not have any effect either on the acquisition or the generalization of fear. Our results suggest that these fear conditioning processes are not impaired in individuals at risk from anxiety. Copyright © 2012 Elsevier B.V. All rights reserved.

Modelling toehold-mediated RNA strand displacement.

PubMed

Šulc, Petr; Ouldridge, Thomas E; Romano, Flavio; Doye, Jonathan P K; Louis, Ard A

2015-03-10

We study the thermodynamics and kinetics of an RNA toehold-mediated strand displacement reaction with a recently developed coarse-grained model of RNA. Strand displacement, during which a single strand displaces a different strand previously bound to a complementary substrate strand, is an essential mechanism in active nucleic acid nanotechnology and has also been hypothesized to occur in vivo. We study the rate of displacement reactions as a function of the length of the toehold and temperature and make two experimentally testable predictions: that the displacement is faster if the toehold is placed at the 5' end of the substrate; and that the displacement slows down with increasing temperature for longer toeholds. Copyright © 2015 Biophysical Society. Published by Elsevier Inc. All rights reserved.

Psychiatric comorbidity of chronic daily headache: focus on traumatic experiences in childhood, post-traumatic stress disorder and suicidality.

PubMed

Juang, Kai Dih; Yang, Chin-Yi

2014-04-01

The fifth edition of the Diagnostic and Statistic Manual (DSM-5) reclassified some mental disorders recently. Post-traumatic stress disorder (PTSD) is in a new section termed "trauma- and stressor-related disorder". Community-based studies have shown that PTSD is associated with a notably high suicidal risk. In addition to previous findings of comorbidity between chronic daily headache (CDH) and both depressive disorders and anxiety disorders, recent data suggest that frequency of childhood maltreatment, PTSD, and suicidality are also increased in CDH. CDH patients with migraine aura are especially at risk of suicidal ideation. Research suggests that migraine attack, aura, frequency, and chronicity may all be related to serotonergic dysfunction. Vulnerability to PTSD and suicidality are also linked to brain serotonin function, including polymorphisms in the serotonin transporter gene (5-HTTLPR). In the present review, we focus on recent advances in knowledge of traumatic experiences in childhood, PTSD, and suicidality in relation to migraine and CDH. We hypothesize that vulnerability to PTSD is associated with migraine attack, migraine aura, and CDH. We further postulate that these associations may explain some of the elevated suicidal risks among patients with migraine, migraine aura, and/or CDH. Field studies are required to support these hypotheses.

An interpersonal perspective on depression: the role of marital adjustment, conflict communication, attributions, and attachment within a clinical sample.

PubMed

Heene, Els; Buysse, Ann; Van Oost, Paulette

2007-12-01

Previous studies have focused on the difficulties in psychosocial functioning in depressed persons, underscoring the distress experienced by both spouses. We selected conflict communication, attribution, and attachment as important domains of depression in the context of marital adjustment, and we analyzed two hypotheses in one single study. First, we analyzed whether a clinical sample of couples with a depressed patient would differ significantly from a control group on these variables. Second, we explored to what degree these variables mediate/moderate the relationship between depressive symptoms and marital adjustment. The perspectives of both spouses were taken into account, as well as gender differences. In total, 69 clinical and 69 control couples were recruited, and a series of multivariate analyses of variance and regression analyses were conducted to test both hypotheses. Results indicated that both patients and their partners reported less marital adjustment associated with more negative perceptions on conflict communication, causal attributions, and insecure attachment. In addition, conflict communication and causal attributions were significant mediators of the association between depressive symptoms and marital adjustment for both depressed men and women, and causal attributions also moderated this link. Ambivalent attachment was a significant mediator only for the female identified patients. Several sex differences and clinical implications are discussed.

Glutathione S-transferases as antioxidant defence agents confer pyrethroid resistance in Nilaparvata lugens.

PubMed Central

Vontas, J G; Small, G J; Hemingway, J

2001-01-01

Selection of a laboratory colony of the brown planthopper Nilaparvata lugens with the pyrethroids permethrin and lambda-cyhalothrin increased its resistance to both insecticides. Biochemical analysis and synergistic studies with metabolic inhibitors indicated that elevated glutathione S-transferases (GSTs) with a predominant peroxidase activity conferred resistance to both pyrethroids, whereas esterases conferred part of the resistance to permethrin. Purified esterases hydrolysed permethrin at a slow rate, but incubation of either pyrethroid or their primary metabolites with partially purified GSTs had no effect on the metabolic profile. Although GSTs were sensitive to inhibition by both pyrethroids, they did not serve as binding proteins, as previously hypothesized [Grant and Matsumura (1988) Insect Biochem. 18, 615-622]. We demonstrate that pyrethroids, in addition to their neurotoxic effect, induce oxidative stress and lipid peroxidation in insects. Pyrethroid exposure induced lipid peroxides, protein oxidation and depleted reduced glutathione. Elevated GSTs in the resistant strains attenuated the pyrethroid-induced lipid peroxidation and reduced mortality, whereas their in vivo inhibition eliminated their protective role. We therefore hypothesize that the main role of elevated GSTs in conferring resistance in N. lugens is through protecting tissues from oxidative damage. Our study extends the GSTs' range of efficacy to pyrethroid insecticides and possibly explains the role of elevated GSTs in other pyrethroid-resistant insects. PMID:11415437

Perfusion information extracted from resting state functional magnetic resonance imaging.

PubMed

Tong, Yunjie; Lindsey, Kimberly P; Hocke, Lia M; Vitaliano, Gordana; Mintzopoulos, Dionyssios; Frederick, Blaise deB

2017-02-01

It is widely known that blood oxygenation level dependent (BOLD) contrast in functional magnetic resonance imaging (fMRI) is an indirect measure for neuronal activations through neurovascular coupling. The BOLD signal is also influenced by many non-neuronal physiological fluctuations. In previous resting state (RS) fMRI studies, we have identified a moving systemic low frequency oscillation (sLFO) in BOLD signal and were able to track its passage through the brain. We hypothesized that this seemingly intrinsic signal moves with the blood, and therefore, its dynamic patterns represent cerebral blood flow. In this study, we tested this hypothesis by performing Dynamic Susceptibility Contrast (DSC) MRI scans (i.e. bolus tracking) following the RS scans on eight healthy subjects. The dynamic patterns of sLFO derived from RS data were compared with the bolus flow visually and quantitatively. We found that the flow of sLFO derived from RS fMRI does to a large extent represent the blood flow measured with DSC. The small differences, we hypothesize, are largely due to the difference between the methods in their sensitivity to different vessel types. We conclude that the flow of sLFO in RS visualized by our time delay method represents the blood flow in the capillaries and veins in the brain.

Phylogeny and systematic position of Opiliones: a combined analysis of chelicerate relationships using morphological and molecular data

NASA Technical Reports Server (NTRS)

Giribet, Gonzalo; Edgecombe, Gregory D.; Wheeler, Ward C.; Babbitt, Courtney

2002-01-01

The ordinal level phylogeny of the Arachnida and the suprafamilial level phylogeny of the Opiliones were studied on the basis of a combined analysis of 253 morphological characters, the complete sequence of the 18S rRNA gene, and the D3 region of the 28S rRNA gene. Molecular data were collected for 63 terminal taxa. Morphological data were collected for 35 exemplar taxa of Opiliones, but groundplans were applied to some of the remaining chelicerate groups. Six extinct terminals, including Paleozoic scorpions, are scored for morphological characters. The data were analyzed using strict parsimony for the morphological data matrix and via direct optimization for the molecular and combined data matrices. A sensitivity analysis of 15 parameter sets was undertaken, and character congruence was used as the optimality criterion to choose among competing hypotheses. The results obtained are unstable for the high-level chelicerate relationships (except for Tetrapulmonata, Pedipalpi, and Camarostomata), and the sister group of the Opiliones is not clearly established, although the monophyly of Dromopoda is supported under many parameter sets. However, the internal phylogeny of the Opiliones is robust to parameter choice and allows the discarding of previous hypotheses of opilionid phylogeny such as the "Cyphopalpatores" or "Palpatores." The topology obtained is congruent with the previous hypothesis of "Palpatores" paraphyly as follows: (Cyphophthalmi (Eupnoi (Dyspnoi + Laniatores))). Resolution within the Eupnoi, Dyspnoi, and Laniatores (the latter two united as Dyspnolaniatores nov.) is also stable to the superfamily level, permitting a new classification system for the Opiliones. c2002 The Willi Hennig Society.

Teaching Rational Number Addition Using Video Games: The Effects of Instructional Variation. CRESST Report 808

ERIC Educational Resources Information Center

Vendlinski, Terry P.; Chung, Greg K. W. K.; Binning, Kevin R.; Buschang, Rebecca E.

2011-01-01

Understanding the meaning of rational numbers and how to perform mathematical operations with those numbers seems to be a perennial problem in the United States for both adults and children. Based on previous work, we hypothesized that giving students more time to practice using rational numbers in an environment that enticed them to apply their…

Developmental Profiles for Multiple Object Tracking and Spatial Memory: Typically Developing Preschoolers and People with Williams Syndrome

ERIC Educational Resources Information Center

O'Hearn, Kirsten; Hoffman, James E.; Landau, Barbara

2010-01-01

The ability to track moving objects, a crucial skill for mature performance on everyday spatial tasks, has been hypothesized to require a specialized mechanism that may be available in infancy (i.e. indexes). Consistent with the idea of specialization, our previous work showed that object tracking was more impaired than a matched spatial memory…

The Interviewer in the Respondent's Shoes: What Can We Learn from the Way Interviewers Answer Survey Questions?

ERIC Educational Resources Information Center

Wuyts, Celine; Loosveldt, Geert

2017-01-01

Previous research shows that interviewers to some extent fail to expend the effort that is needed to collect high-quality survey data. We extend the idea of interviewer satisficing to a related task, in which the interviewers themselves answer survey questions. We hypothesize that interviewers who self-administer the questionnaire in a careless…

Insulin and insulin-like growth factor-I (IGF-I) receptor phosphorylation in µ-calpain knockout mice

USDA-ARS?s Scientific Manuscript database

Numerous cellular processes are controlled by insulin and IGF-I signaling pathways. Due to previous work in our laboratories, we hypothesized that insulin (IR) and type 1 IGF-I (IGF-IR) receptor signaling is decreased due to increased protein tyrosine phosphatase 1B (PTP1B) activity. C57BL/6J mice...

Sampling affects the detection of genetic subdivision and conservation implications for fisher in the Sierra Nevada

Treesearch

Jody M. Tucker; Michael K. Schwartz; Richard L. Truex; Samantha M. Wisely; Fred W. Allendorf

2014-01-01

The small population of fisher (Pekania pennanti) in the southern Sierra Nevada is completely geographically and genetically isolated putting it at increased risk of extinction. Previous research using a clustered sampling scheme found a high amount of genetic subdivision within the southern Sierra Nevada population hypothesized to be caused by the Kings River Canyon....

Real and Fictive Motion Processing in Polish L2 Users of English and Monolinguals: Evidence for Different Conceptual Representations

ERIC Educational Resources Information Center

Tomczak, Ewa; Ewert, Anna

2015-01-01

We examine cross-linguistic influence in the processing of motion sentences by L2 users from an embodied cognition perspective. The experiment employs a priming paradigm to test two hypotheses based on previous action and motion research in cognitive psychology. The first hypothesis maintains that conceptual representations of motion are embodied…

Differential and Dose-Dependent Inflammatory Responses in a Mouse Model of Respirable Instillation of Environmental Diesel, Emission-Source Diesel , Emmission-Source Diesel and Ambient Air Pollution Particles In Vivo.

EPA Science Inventory

Rationale: Previously, we found that ambient particulate matter (APM) activates pulmonary dendritic cells in vitro. We hypothesized that single acute exposures to PM would promote inflammatory activation of the lung in vivo and provide information on early immunological events of...

"Smoking": Use of Cigarettes, Cigars and Blunts among Southeast Asian American Youth and Young Adults

ERIC Educational Resources Information Center

Lee, J. P.; Battle, R. S.; Lipton, R.; Soller, B.

2010-01-01

Increased use of cigars has been noted among youth, as well as use of blunts (hollowed-out cigars filled with marijuana). Three types of relationships have been previously hypothesized between use of tobacco and marijuana in substance use progression. We aimed to assess these relationships for Southeast Asian American youth and adults in an urban…

A Sense of Belonging: How Student Feelings Correlate with Learning about Race

ERIC Educational Resources Information Center

Kernahan, Cyndi; Zheng, Wei; Davis, Tricia

2014-01-01

Learning about race and racism can be a difficult process. Previous work has shown that courses in this area can help to increase awareness of racial bias and discrimination, but less work has focused on how that change occurs. We hypothesized that feelings of belonging within the classroom could correlate with student learning and our results…

THE EFFECT OF ATRAZINE ON PUBERTY IN THE MALE WISTAR RATS: AN EVALUATION IN THE PROTOCOL FOR THE ASSESSMENT OF PUBERTAL DEVELOPMENT AND THYROID FUNCTION

EPA Science Inventory

Since atrazine (ATR), a chlorotriazine herbicide, has been shown previously to alter the secretion of luteinizing hormone (LH) and prolactin (PRL) through a direct effect on the central nervous system (CNS), we hypothesized that exposure to ATR in the EDSTAC male pubertal protoco...

Homosexual Fellatio: Erect Penis Licking between Male Bonin Flying Foxes Pteropus pselaphon

PubMed Central

Sugita, Norimasa

2016-01-01

A recent focus of interest has been on the functional significance of genital licking (fellatio and cunnilingus) in relation to sexual selection in Pteropodid bats. In the present paper, a form of fellatio in wild Bonin flying foxes, Pteropus pselaphon, performed between adult males has been reported. During the mating season, adult flying foxes roost in same-sex groups, forming ball-shaped clusters which provide warmth. The female clusters may also contain a few males. Unassociated with allogrooming, same-sex genital licking occurred among males in the all male clusters. As such, male-male fellatio can be considered as homosexual behavior, two functional explanations could account for this behavior; the social bonding and the social tension regulation hypotheses suggested in a previous review. Given that neither the simpler alternative that in all male groups such fellatio may represent misdirected sexual behavior, nor the two previously proposed functional hypotheses were supported by the data, I propose another functional hypothesis. Homosexual fellatio in this species could help males solve inconsistent situations in the roost when there are conflicts between cooperative behavior for social thermoregulation and competition for mating. PMID:27824953

Psychobiological mechanisms of exercise dependence.

PubMed

Hamer, Mark; Karageorghis, Costas I

2007-01-01

Exercise dependence (ED) is characterised by an obsessive and unhealthy preoccupation with exercise. Previous research has focused largely on identifying behavioural aspects of ED, although the biological mechanisms remain unknown and are under researched. We review various ED hypotheses including affect regulation, anorexia analogue, sympathetic arousal and beta-endorphin. We also present a novel hypothesis pertaining to ED and interleukin (IL)-6, which combines previous hypotheses with literature from the field of psycho-neuroimmunology. We explore the notion that IL-6 provides a link from the periphery to the brain, which may mediate the underlying features of ED. We propose a conceptual model indicating that, in individuals prone to ED, exercise results in a transient reduction in negative affect, but concurrently results in excessive production of IL-6 and the activation of neuroendocrine pathways, which are associated with behavioural and psychological disturbances of exercise withdrawal. Our intention is for this model to serve as a basis for further research in the area of ED, which may eventually lead to the development of successful treatment strategies. Recent developments in methods to reliably assess these biological markers from blood and saliva samples should encourage such research to be undertaken in exercise settings.

Phylogeny of the Ampelocissus-Vitis clade in Vitaceae supports the New World origin of the grape genus.

PubMed

Liu, Xiu-Qun; Ickert-Bond, Stefanie M; Nie, Ze-Long; Zhou, Zhuo; Chen, Long-Qing; Wen, Jun

2016-02-01

The grapes and the close allies in Vitaceae are of great agronomic and economic importance. Our previous studies showed that the grape genus Vitis was closely related to three tropical genera, which formed the Ampelocissus-Vitis clade (including Vitis, Ampelocissus, Nothocissus and Pterisanthes). Yet the phylogenetic relationships of the four genera within this clade remain poorly resolved. Furthermore, the geographic origin of Vitis is still controversial, because the sampling of the close relatives of Vitis was too limited in the previous studies. This study reconstructs the phylogenetic relationships within the clade, and hypothesizes the origin of Vitis in a broader phylogenetic framework, using five plastid and two nuclear markers. The Ampelocissus-Vitis clade is supported to be composed of five main lineages. Vitis includes two described subgenera each as a monophyletic group. Ampelocissus is paraphyletic. The New World Ampelocissus does not form a clade and shows a complex phylogenetic relationship, with A. acapulcensis and A. javalensis forming a clade, and A. erdvendbergiana sister to Vitis. The majority of the Asian Ampelocissus species form a clade, within which Pterisanthes is nested. Pterisanthes is polyphyletic, suggesting that the lamellate inflorescence characteristic of the genus represents convergence. Nothocissus is sister to the clade of Asian Ampelocissus and Pterisanthes. The African Ampelocissus forms a clade with several Asian species. Based on the Bayesian dating and both the RASP and Lagrange analyses, Vitis is inferred to have originated in the New World during the late Eocene (39.4Ma, 95% HPD: 32.6-48.6Ma), then migrated to Eurasia in the late Eocene (37.3Ma, 95% HPD: 30.9-45.1Ma). The North Atlantic land bridges (NALB) are hypothesized to be the most plausible route for the Vitis migration from the New World to Eurasia, while intercontinental long distance dispersal (LDD) cannot be eliminated as a likely mechanism. Copyright © 2015 Elsevier Inc. All rights reserved.

Oral microbial community assembly under the influence of periodontitis.

PubMed

Chen, Hongju; Peng, Shuting; Dai, Lin; Zou, Quan; Yi, Bin; Yang, Xianghong; Ma, Zhanshan Sam

2017-01-01

Several ecological hypotheses (e.g., specific plaque, non-specific plaque and keystone pathogen) regarding the etiology of periodontitis have been proposed since the 1990s, most of which have been centered on the concept of dysbiosis associated with periodontitis. Nevertheless, none of the existing hypotheses have presented mechanistic interpretations on how and why dysbiosis actually occurs. Hubbell's neutral theory of biodiversity offers a powerful null model to test hypothesis regarding the mechanism of community assembly and diversity maintenance from the metagenomic sequencing data, which can help to understand the forces that shape the community dynamics such as dysbiosis. Here we reanalyze the dataset from Abusleme et al.'s comparative study of the oral microbial communities from periodontitis patients and healthy individuals. Our study demonstrates that 14 out of 61 communities (23%) passed the neutrality test, a percentage significantly higher than the previous reported neutrality rate of 1% in human microbiome (Li & Ma 2016, Scientific Reports). This suggests that, while the niche selection may play a predominant role in the assembly and diversity maintenance in oral microbiome, the effect of neutral dynamics may not be ignored. However, no statistically significant differences in the neutrality passing rates were detected between the periodontitis and healthy treatments with Fisher's exact probability test and multiple testing corrections, suggesting that the mechanism of community assembly is robust against disturbances such as periodontitis. In addition, our study confirmed previous finding that periodontitis patients exhibited higher biodiversity. These findings suggest that while periodontitis may significantly change the community composition measured by diversity (i.e., the exhibition or 'phenotype' of community assembly), it does not seem to cause the 'mutation' of the 'genotype" (mechanism) of community assembly. We argue that the 'phenotypic' changes explain the observed link (not necessarily causal) between periodontitis and community dysbiosis, which is certainly worthy of further investigation.

Oral microbial community assembly under the influence of periodontitis

PubMed Central

Chen, Hongju; Peng, Shuting; Dai, Lin; Zou, Quan; Yi, Bin; Yang, Xianghong

2017-01-01

Several ecological hypotheses (e.g., specific plaque, non-specific plaque and keystone pathogen) regarding the etiology of periodontitis have been proposed since the 1990s, most of which have been centered on the concept of dysbiosis associated with periodontitis. Nevertheless, none of the existing hypotheses have presented mechanistic interpretations on how and why dysbiosis actually occurs. Hubbell’s neutral theory of biodiversity offers a powerful null model to test hypothesis regarding the mechanism of community assembly and diversity maintenance from the metagenomic sequencing data, which can help to understand the forces that shape the community dynamics such as dysbiosis. Here we reanalyze the dataset from Abusleme et al.’s comparative study of the oral microbial communities from periodontitis patients and healthy individuals. Our study demonstrates that 14 out of 61 communities (23%) passed the neutrality test, a percentage significantly higher than the previous reported neutrality rate of 1% in human microbiome (Li & Ma 2016, Scientific Reports). This suggests that, while the niche selection may play a predominant role in the assembly and diversity maintenance in oral microbiome, the effect of neutral dynamics may not be ignored. However, no statistically significant differences in the neutrality passing rates were detected between the periodontitis and healthy treatments with Fisher’s exact probability test and multiple testing corrections, suggesting that the mechanism of community assembly is robust against disturbances such as periodontitis. In addition, our study confirmed previous finding that periodontitis patients exhibited higher biodiversity. These findings suggest that while periodontitis may significantly change the community composition measured by diversity (i.e., the exhibition or ‘phenotype’ of community assembly), it does not seem to cause the ‘mutation’ of the ‘genotype” (mechanism) of community assembly. We argue that the ‘phenotypic’ changes explain the observed link (not necessarily causal) between periodontitis and community dysbiosis, which is certainly worthy of further investigation. PMID:28813450

New Data on the Presence of Hemocyanin in Plecoptera: Recomposing a Puzzle

PubMed Central

Amore, Valentina; Gaetani, Brunella; Angeles Puig, Maria; Fochetti, Romolo

2011-01-01

The specific role of hemocyanin in Plecoptera (stoneflies) is still not completely understood, since none of the hypotheses advanced have proven fully convincing. Previous data show that mRNA hemocyanin sequences are not present in all Plecoptera, and that hemocyanin does not seem to be uniformly distributed within the order. All species possess hexamerins, which are multifunction proteins that probably originated from hemocyanin. In order to obtain an increasingly detailed picture on the presence and distribution of hemocyanin across the order, this study presents new data regarding nymphs and adults of selected Plecoptera species. Results confirm that the hemocyanin expression differs among nymphs in the studied stonefly species. Even though previous studies have found hemocyanin in adults of two stonefly species it was not detected in the present study, even in species where nymphs show hemocyanin, suggesting that the physiological need of this protein can change during life cycle. The phylogenetic pattern obtained using hemocyanin sequences matches the accepted scheme of traditional phylogeny based on morphology, anatomy, and biology. It is remarkable to note that the hemocyanin conserved region acts like a phylogenetic molecular marker within Plecoptera. PMID:22236413

Delay of gratification by orangutans (Pongo pygmaeus) in the accumulation task.

PubMed

Parrish, Audrey E; Perdue, Bonnie M; Stromberg, Erin E; Bania, Amanda E; Evans, Theodore A; Beran, Michael J

2014-05-01

There is considerable evidence indicating that chimpanzees can delay gratification for extended time intervals, particularly in the accumulation task in which food items accumulate within a participant's reach until the participant begins to consume them. However, there is limited evidence that other ape species might also exhibit this capacity, despite there being a number of similar studies indicating that nonape species (e.g., monkeys and birds) can delay gratification, but not for nearly as long as chimpanzees. To help define the taxonomic distribution of delay of gratification behavior in the order Primates, we tested 6 orangutans in the current experiments and compared their performance with comparable data from a previous study with capuchin monkeys. We varied delay length and visibility of the items that were still available for accumulation to determine the impact of these factors on performance. Species differences on the accumulation task emerged when comparing the current data to data from a previous study. Orangutans outperformed capuchin monkeys, suggesting that ape species may generally show better delay of gratification and delay maintenance abilities than monkeys. However, more studies are necessary to rule out alternative hypotheses on the distribution of delay maintenance abilities across primate species. ©2014 APA, all rights reserved.

Friends First? The Peer Network Origins of Adolescent Dating

PubMed Central

Kreager, Derek A.; Molloy, Lauren E.; Moody, James; Feinberg, Mark E.

2015-01-01

The proximity of dating partners in peer friendship networks has important implications for the diffusion of health-risk behaviors and adolescent social development. We derive two competing hypotheses for the friendship-romance association. The first predicts that daters are proximally positioned in friendship networks prior to dating and that opposite-gender friends are likely to transition to dating. The second predicts that dating typically crosses group boundaries and opposite-gender friends are unlikely to later date. We test these hypotheses with longitudinal friendship data for 626 9th grade PROSPER heterosexual dating couples. Results primarily support the second hypothesis: romantic partners are unlikely to be friends in the previous year or share the same cohesive subgroup, and opposite-gender friends are unlikely to transition into dating. PMID:27134511

An exploratory analysis of the relationship between ambient ...

EPA Pesticide Factsheets

Background: Associations between ozone (O3) and fine particulate matter (PM2.5) concentrations and birth outcomes have been previously demonstrated. We perform an exploratory analysis of O3 and PM2.5 concentrations during early pregnancy and multiple types of birth defects. Methods: Data on births were obtained from the Texas Birth Defects Registry and the National Birth Defects Prevention Study (NBDPS) in Texas. Air pollution concentrations were determined using a Bayesian hierarchical model that combined modeled air pollution concentrations with air monitoring data to create bias-corrected concentrations and matched to residential address at birth. Average air pollution concentrations during the first trimester were calculated. Results: The analysis generated hypotheses for future, confirmatory studies; although many of the observed associations between the air pollutants and birth defects were null. The hypotheses are provided by an observed association between O3 and craniosynostosis [adjusted OR 1.28 (95% CI 1.04, 1.58) per 13.3 ppb increase) and observed inverse associations between PM2.5 concentrations and septal heart defects and obstructive heart defects [adjusted ORs 0.79 (95% CI 0.75, 0.82) and 0.88 (95% CI 0.79, 0.97) per 5.0 µg/m3 increase, respectively] in the Texas Birth Defects Registry study. Septal heart defects and ventricular outflow tract obstructions were also examined using the NBDPS but the associations with PM2.5 were null [adj

Affect-related synesthesias: a prospective view on their existence, expression and underlying mechanisms

PubMed Central

Dael, Nele; Sierro, Guillaume; Mohr, Christine

2013-01-01

The literature on developmental synesthesia has seen numerous sensory combinations, with surprisingly few reports on synesthesias involving affect. On the one hand, emotion, or more broadly affect, might be of minor importance to the synesthetic experience (e.g., Sinke et al., 2012). On the other hand, predictions on how affect could be relevant to the synesthetic experience remain to be formulated, in particular those that are driven by emotion theories. In this theoretical paper, we hypothesize that a priori studies on synesthesia involving affect will observe the following. Firstly, the synesthetic experience is not merely about discrete emotion processing or overall valence (positive, negative) but is determined by or even altered through cognitive appraisal processes. Secondly, the synesthetic experience changes temporarily on a quantitative level according to (i) the affective appraisal of the inducing stimulus or (ii) the current affective state of the individual. These hypotheses are inferred from previous theoretical and empirical accounts on synesthesia (including the few examples involving affect), different emotion theories, crossmodal processing accounts in synesthetes, and non-synesthetes, and the presumed stability of the synesthetic experience. We hope that the current review will succeed in launching a new series of studies on “affective synesthesias.” We particularly hope that such studies will apply the same creativity in experimental paradigms as we have seen and still see when assessing and evaluating “traditional” synesthesias. PMID:24151478

CRevolution 2—Origin and evolution of the Colorado River system, workshop abstracts

USGS Publications Warehouse

Beard, L. Sue; Karlstrom, Karl E.; Young, Richard A.; Billingsley, George H.

2011-01-01

A 2010 Colorado River symposium, held in Flagstaff, Arizona, involved 70 participants who engaged in intense debate about the origin and evolution of the Colorado River system. This symposium, built upon two previous decadal scientific meetings, focused on forging scientific consensus, where possible, while articulating continued controversies regarding the Cenozoic evolution of the Colorado River System and the landscapes of the Colorado Plateau-Rocky Mountain region that it drains. New developments involved hypotheses that Neogene mantle flow is driving plateau tilting and differential uplift and new and controversial hypotheses for the pre-6 Ma presence and evolution of ancestral rivers that may be important in the history and birth of the present Colorado River. There is a consensus that plateau tilt and uplift models must be tested with multidisciplinary studies involving differential incision studies and additional geochronology and thermochronology to determine the relative importance of tectonic and geomorphic forces that shape the spectacular landscapes of the Colorado Plateau, Arizona and region. In addition to the scientific goals, the meeting participants emphasized the iconic status of Grand Canyon for geosciences and the importance of good communication between the research community, the geoscience education/interpretation community, the public, and the media. Building on a century-long tradition, this region still provides a globally important natural laboratory for studies of the interactions of erosion and tectonism in shaping the landscape of elevated plateaus.

Previous exposure to the World Trade Center terrorist attack and posttraumatic symptoms among older adults following Hurricane Sandy.

PubMed

Shrira, Amit; Palgi, Yuval; Hamama-Raz, Yaira; Goodwin, Robin; Ben-Ezra, Menachem

2014-01-01

The present study tested the maturation and inoculation hypotheses by examining whether age and previous exposure to the September 11, 2001, World Trade Center (WTC) terrorist attack moderated the relationship between degree of exposure to Hurricane Sandy and related posttraumatic stress disorder (PTSD) symptoms. An online sample of 1,000 participants from affected states completed self-report questionnaires one month after Hurricane Sandy hit the East Coast. Participants reported their degree of exposure to the WTC terrorist attack and to Hurricane Sandy, and their posttraumatic stress disorder (PTSD) symptoms following Hurricane Sandy. The positive relationship between degree of exposure to Hurricane Sandy and level of PTSD symptoms was weaker among older adults. An additional significant three-way interaction suggested that both age and previous exposure to the WTC terrorist attack moderated the relationship between degree of exposure to Hurricane Sandy and level of PTSD symptoms. Previous high degree of exposure to the WTC terrorist attack was related to a weaker effect of current exposure to Hurricane Sandy on PTSD symptoms among older adults. However, among younger adults, previous high degree of exposure to the WTC terrorist attack was related to a stronger effect of current exposure on PTSD symptoms. When confronted by a natural disaster, American older adults are generally resilient. Supporting the inoculation hypothesis, resilience of older adults may be partly related to the strength successfully extracted from previous exposure to adverse events.

A Study of Individual Responses to Bullying as a Function of Teacher Burnout

ERIC Educational Resources Information Center

Rice, Wanda J.

2013-01-01

It is hypothesized that factors related to teacher burnout influence responses to bullying behaviors. This study hypothesizes that teachers with a higher degree of burnout are less likely to respond to bullying behaviors and it further hypothesizes that those with greater years of teaching are less likely to respond to bullying behaviors. Of…

Shedding new light on rapidly resolving traumatic acute subdural hematomas.

PubMed

Brooke, Magdalene; Patel, Atul; Castro-Moure, Federico; Victorino, Gregory P

2017-11-01

Rapidly resolving acute subdural hematomas (RRASDHs) have been described in case reports and case series but are still poorly understood. We hypothesized that a cohort analysis would confirm previously reported predictors of RRASDH including coagulopathy, additional intracranial hemorrhage, and low-density band on imaging. We also hypothesized that rapid resolution would be associated with improved trauma outcomes. We reviewed all nonoperative acute subdural hematomas (ASDHs) treated at our center from 2011 to 2015. Inclusion criteria were ASDH on computed tomography (CT), admission Glasgow coma score >7, and repeat CT to evaluate ASDH change. RRASDH was defined as reduced hematoma thickness by 50% within 72 h. Clinical data, CT findings, and trauma end points were analyzed for the RRASDH and nonresolving groups. There were 154 ASDH patients included, with 29 cases of RRASDH. The RRASDH group had a lower rate of comorbidities than the nonresolving group (58.6% versus 78.4%, P = 0.03) and a lower rate of prehospital anticoagulation (7.7% versus 37.1%, P = 0.004). Previously reported predictors of RRASDH did not differ between the groups, nor did any clinical outcome measures. When compared with patients who experienced rapid growth (>50% increased width in 72 h), the RRASDH group had lower mortality (3.4% versus 23.5%, P = 0.04). To our knowledge, this is the largest review of RRASDHs. We identified two previously unrecognized factors that may predict resolution; however, previously reported predictors were not associated with resolution. We also found no relationship between RRASDHs and improved standard trauma outcomes, calling into question the clinical significance of RRASDH. Copyright © 2017 Elsevier Inc. All rights reserved.

On the origin and age of the Great Sand Dunes, Colorado

USGS Publications Warehouse

Madole, R.F.; Romig, J.H.; Aleinikoff, J.N.; VanSistine, D.P.; Yacob, E.Y.

2008-01-01

Over the past 100??yr, several hypotheses have been proposed for the origin and age of the Great Sand Dunes. These hypotheses differ widely in the descriptions of dune morphometry, the immediate source of eolian sand, and when sand transport occurred. The primary purpose of this paper is to evaluate these hypotheses and, where warranted, to present new ideas about the origin and age of the Great Sand Dunes. To evaluate the previous hypotheses, we had to develop more detailed information about the surficial geology of the northern San Luis Valley. Thus, we mapped the surficial geology of an area extending several tens of kilometers north, south, and west of the Great Sand Dunes and examined subsurface stratigraphy in more than 200 wells and borings. In addition, we used relative-dating criteria and several radiocarbon and OSL ages to establish the chronology of surficial deposits, and we determined the U-Pb ages of detrital zircons to obtain information about the sources of the sand in the Great Sand Dunes. The first principal finding of this study is that the lower part of the closed basin north of the Rio Grande, referred to here as the sump, is the immediate source of the sand in the Great Sand Dunes, rather than the late Pleistocene flood plain of the Rio Grande (the most widely accepted hypothesis). A second principal finding is that the Great Sand Dunes are older than late Pleistocene. They postdate the draining of Lake Alamosa, which began ??? 440??ka, and predate the time when streams draining the west flank of the Sangre de Cristo Mountains were deflected by incipient dunes that formed near the mountain front. Geomorphic and stratigraphic evidence indicate that this deflection occurred prior to the end of the next to last glaciation (Bull Lake), i.e., prior to ??? 130??ka.

The Sex Determination Gene Shows No Founder Effect in the Giant Honey Bee, Apis dorsata

PubMed Central

Yan, Wei Yu; Wu, Xiao Bo; Zeng, Zhi Jiang; Huang, Zachary Y.

2012-01-01

Background All honey bee species (Apis spp) share the same sex determination mechanism using the complementary sex determination (csd) gene. Only individuals heterogeneous at the csd allele develop into females, and the homozygous develop into diploid males, which do not survive. The honeybees are therefore under selection pressure to generate new csd alleles. Previous studies have shown that the csd gene is under balancing selection. We hypothesize that due to the long separation from the mainland of Hainan Island, China, that the giant honey bees (Apis dorsata) should show a founder effect for the csd gene, with many different alleles clustered together, and these would be absent on the mainland. Methodology/Principal Findings We sampled A. dorsata workers from both Hainan and Guangxi Provinces and then cloned and sequenced region 3 of the csd gene and constructed phylogenetic trees. We failed to find any clustering of the csd alleles according to their geographical origin, i.e. the Hainan and Guangxi samples did not form separate clades. Further analysis by including previously published csd sequences also failed to show any clade-forming in both the Philippines and Malaysia. Conclusions/Significance Results from this study and those from previous studies did not support the expectations of a founder effect. We conclude that because of the extremely high mating frequency of A. dorsata queens, a founder effect does not apply in this species. PMID:22511940

The sex determination gene shows no founder effect in the giant honey bee, Apis dorsata.

PubMed

Liu, Zhi Yong; Wang, Zi Long; Yan, Wei Yu; Wu, Xiao Bo; Zeng, Zhi Jiang; Huang, Zachary Y

2012-01-01

All honey bee species (Apis spp) share the same sex determination mechanism using the complementary sex determination (csd) gene. Only individuals heterogeneous at the csd allele develop into females, and the homozygous develop into diploid males, which do not survive. The honeybees are therefore under selection pressure to generate new csd alleles. Previous studies have shown that the csd gene is under balancing selection. We hypothesize that due to the long separation from the mainland of Hainan Island, China, that the giant honey bees (Apis dorsata) should show a founder effect for the csd gene, with many different alleles clustered together, and these would be absent on the mainland. We sampled A. dorsata workers from both Hainan and Guangxi Provinces and then cloned and sequenced region 3 of the csd gene and constructed phylogenetic trees. We failed to find any clustering of the csd alleles according to their geographical origin, i.e. the Hainan and Guangxi samples did not form separate clades. Further analysis by including previously published csd sequences also failed to show any clade-forming in both the Philippines and Malaysia. Results from this study and those from previous studies did not support the expectations of a founder effect. We conclude that because of the extremely high mating frequency of A. dorsata queens, a founder effect does not apply in this species.

Alkaloids from psychotria target sirtuins: in silico and in vitro interaction studies.

PubMed

Sacconnay, Lionel; Ryckewaert, Lucie; Dos Santos Passos, Carolina; Guerra, Maria Cristina; Kato, Lucilia; Alves de Oliveira, Cecilia Maria; Henriques, Amélia; Carrupt, Pierre-Alain; Simões-Pires, Claudia; Nurisso, Alessandra

2015-04-01

Epigenetic enzymes such as histone deacetylases play a crucial role in the development of ageing-related diseases. Among the 18 histone deacetylase isoforms found in humans, class III histone deacetylases, also known as sirtuins, seem to be promising targets for treating neurodegenerative conditions. Recently, Psychotria alkaloids, mainly monoterpene indoles, have been reported for their inhibitory properties against central nervous system cholinesterase and monoamine oxidase proteins. Given the multifunctional profile of these alkaloids in the central nervous system, and the fact that the indole scaffold has been previously associated with sirtuin inhibition, we hypothesized that these indole derivatives could also interact with sirtuins. In the present study, alkaloids previously isolated from Psychotria spp. were evaluated for their potential interaction with human sirtuin 1 and sirtuin 2 by molecular docking and molecular dynamics simulation approaches. The in silico results allowed for the selection of five potentially active compounds, namely, prunifoleine, 14-oxoprunifoleine, E-vallesiachotamine, Z-vallesiachotamine, and vallesiachotamine lactone. The sirtuin inhibition of these compounds was confirmed in vitro in a dose-response manner, with preliminary information on their pharmacokinetics properties. Georg Thieme Verlag KG Stuttgart · New York.

Positivity effect in healthy aging in observational but not active feedback-learning.

PubMed

Bellebaum, Christian; Rustemeier, Martina; Daum, Irene

2012-01-01

The present study investigated the impact of healthy aging on the bias to learn from positive or negative performance feedback in observational and active feedback learning. In active learning, a previous study had already shown a negative learning bias in healthy seniors older than 75 years, while no bias was found for younger seniors. However, healthy aging is accompanied by a 'positivity effect', a tendency to primarily attend to stimuli with positive valence. Based on recent findings of dissociable neural mechanisms in active and observational feedback learning, the positivity effect was hypothesized to influence older participants' observational feedback learning in particular. In two separate experiments, groups of young (mean age 27) and older participants (mean age 60 years) completed an observational or active learning task designed to differentially assess positive and negative learning. Older but not younger observational learners showed a significant bias to learn better from positive than negative feedback. In accordance with previous findings, no bias was found for active learning. This pattern of results is discussed in terms of differences in the neural underpinnings of active and observational learning from performance feedback.

Negative relationships between population density and metabolic rates are not general.

PubMed

Yashchenko, Varvara; Fossen, Erlend Ignacio; Kielland, Øystein Nordeide; Einum, Sigurd

2016-07-01

Population density has recently been suggested to be an important factor influencing metabolic rates and to represent an important 'third axis' explaining variation beyond that explained by body mass and temperature. In situations where population density influences food consumption, the immediate effect on metabolism acting through specific dynamic action (SDA), and downregulation due to fasting over longer periods, is well understood. However, according to a recent review, previous studies suggest a more general effect of population density per se, even in the absence of such effects. It has been hypothesized that this results from animals performing anticipatory responses (i.e. reduced activity) to expected declines in food availability. Here, we test the generality of this finding by measuring density effects on metabolic rates in 10 clones from two different species of the zooplankton Daphnia (Daphnia pulex Leydig and D. magna Straus). Using fluorescence-based respirometry, we obtain high-precision measures of metabolism. We also identify additional studies on this topic that were not included in the previous review, compare the results and evaluate the potential for measurement bias in all previous studies. We demonstrate significant variation in mass-specific metabolism among clones within both species. However, we find no evidence for a negative relationship between population density and mass-specific metabolism. The previously reported pattern also disappeared when we extended the set of studies analysed. We discuss potential reasons for the discrepancy among studies, including two main sources of potential bias (microbial respiration and declining oxygen consumption due to reduced oxygen availability). Only one of the previous studies gives sufficient information to conclude the absence of such biases, and consistent with our results, no effect of density on metabolism was found. We conclude that population density per se does not have a general effect on mass-specific metabolic rate. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

Longitudinal associations between resilience and quality of life in eating disorders.

PubMed

Calvete, Esther; Las Hayas, Carlota; Gómez Del Barrio, Andrés

2018-01-01

This study examined the longitudinal reciprocal associations between resilience factors, quality of life (QoL) domains, and symptoms of eating disorders (EDs). Hypotheses included predictive paths from resilience factors of "acceptance of self and life" and "personal competence" to increased QoL and predictive paths from previous levels of QoL to resilience. A total of 184 patients with EDs (mean age = 29.55, SD = 9.17, 94.8% women) completed measures of resilience, QoL, and EDs symptoms over three waves spaced six month apart. Hypotheses were tested by path analysis. Resilience factors predicted improvements in psychological health and social relationship domains of QoL and a reduction of ED symptoms over time. In addition, psychological health increased acceptance of self and life consistently over time, whereas physical health increased the competence component of resilience. The relationships between resilience factors and QoL are reciprocal, with several mediational paths. A spiral of recursive influences between resilience factors and QoL can take place in people with EDs. This possibility offers new perspectives to understanding the process of recovery in patients with ED. Copyright © 2017 Elsevier B.V. All rights reserved.

Plant ecosystem responses to rising atmospheric CO2: applying a "two-timing" approach to assess alternative hypotheses for mechanisms of nutrient limitation

NASA Astrophysics Data System (ADS)

Medlyn, B.; Jiang, M.; Zaehle, S.

2017-12-01

There is now ample experimental evidence that the response of terrestrial vegetation to rising atmospheric CO2 concentration is modified by soil nutrient availability. How to represent nutrient cycling processes is thus a key consideration for vegetation models. We have previously used model intercomparison to demonstrate that models incorporating different assumptions predict very different responses at Free-Air CO2 Enrichment experiments. Careful examination of model outputs has provided some insight into the reasons for the different model outcomes, but it is difficult to attribute outcomes to specific assumptions. Here we investigate the impact of individual assumptions in a generic plant carbon-nutrient cycling model. The G'DAY (Generic Decomposition And Yield) model is modified to incorporate alternative hypotheses for nutrient cycling. We analyse the impact of these assumptions in the model using a simple analytical approach known as "two-timing". This analysis identifies the quasi-equilibrium behaviour of the model at the time scales of the component pools. The analysis provides a useful mathematical framework for probing model behaviour and identifying the most critical assumptions for experimental study.

Taking the load off: investigations of how adaptive cruise control affects mental workload.

PubMed

Young, Mark S; Stanton, Neville A

2004-07-15

It has been posited that Adaptive Cruise Control (ACC) represents a new generation of vehicle automation, in that it has the potential to relieve drivers of mental as well as physical workload. The results of previous research however, have raised some confusing issues about the specific effects of Adaptive Cruise Control (ACC) on driver mental workload (MWL)--some studies report reduced MWL compared to manual driving, while others find no effect. Two hypotheses are proposed in an attempt to explain these discrepancies: (a) that any potential MWL reductions due to ACC could be masked by the overriding influence of steering demand; or (b) that the tasks designed in some experiments do not exploit the adaptive nature of the ACC system, therefore precluding any potential benefits. Two related experiments were designed to test these hypotheses. It was found that the main reason for the discrepant findings was the nature of the driving task chosen--constant-speed tasks do not realise the mental workload benefits of ACC. Future researchers using ACC devices are advised to use variable-speed tasks to ensure that all aspects of device functionality are covered.

Inferring 'weak spots' in phylogenetic trees: application to mosasauroid nomenclature.

PubMed

Madzia, Daniel; Cau, Andrea

2017-01-01

Mosasauroid squamates represented the apex predators within the Late Cretaceous marine and occasionally also freshwater ecosystems. Proper understanding of the origin of their ecological adaptations or paleobiogeographic dispersals requires adequate knowledge of their phylogeny. The studies assessing the position of mosasauroids on the squamate evolutionary tree and their origins have long given conflicting results. The phylogenetic relationships within Mosasauroidea, however, have experienced only little changes throughout the last decades. Considering the substantial improvements in the development of phylogenetic methodology that have undergone in recent years, resulting, among others, in numerous alterations in the phylogenetic hypotheses of other fossil amniotes, we test the robustness in our understanding of mosasauroid beginnings and their evolutionary history. We re-examined a data set that results from modifications assembled in the course of the last 20 years and performed multiple parsimony analyses and Bayesian tip-dating analysis. Following the inferred topologies and the 'weak spots' in the phylogeny of mosasauroids, we revise the nomenclature of the 'traditionally' recognized mosasauroid clades, to acknowledge the overall weakness among branches and the alternative topologies suggested previously, and discuss several factors that might have an impact on the differing phylogenetic hypotheses and their statistical support.

Energy efficiency drives the global seasonal distribution of birds.

PubMed

Somveille, Marius; Rodrigues, Ana S L; Manica, Andrea

2018-06-01

The uneven distribution of biodiversity on Earth is one of the most general and puzzling patterns in ecology. Many hypotheses have been proposed to explain it, based on evolutionary processes or on constraints related to geography and energy. However, previous studies investigating these hypotheses have been largely descriptive due to the logistical difficulties of conducting controlled experiments on such large geographical scales. Here, we use bird migration-the seasonal redistribution of approximately 15% of bird species across the world-as a natural experiment for testing the species-energy relationship, the hypothesis that animal diversity is driven by energetic constraints. We develop a mechanistic model of bird distributions across the world, and across seasons, based on simple ecological and energetic principles. Using this model, we show that bird species distributions optimize the balance between energy acquisition and energy expenditure while taking into account competition with other species. These findings support, and provide a mechanistic explanation for, the species-energy relationship. The findings also provide a general explanation of migration as a mechanism that allows birds to optimize their energy budget in the face of seasonality and competition. Finally, our mechanistic model provides a tool for predicting how ecosystems will respond to global anthropogenic change.

Globigerinoides ruber morphotypes in the Gulf of Mexico: a test of null hypothesis

USGS Publications Warehouse

Thirumalai, Kaustubh; Richey, Julie N.; Quinn, Terrence M.; Poore, Richard Z.

2014-01-01

Planktic foraminifer Globigerinoides ruber (G. ruber), due to its abundance and ubiquity in the tropical/subtropical mixed layer, has been the workhorse of paleoceanographic studies investigating past sea-surface conditions on a range of timescales. Recent geochemical work on the two principal white G. ruber (W) morphotypes, sensu stricto (ss) and sensu lato (sl), has hypothesized differences in seasonal preferences or calcification depths, implying that reconstructions using a non-selective mixture of morphotypes could potentially be biased. Here, we test these hypotheses by performing stable isotope and abundance measurements on the two morphotypes in sediment trap, core-top, and downcore samples from the northern Gulf of Mexico. As a test of null hypothesis, we perform the same analyses on couplets of G. ruber (W) specimens with attributes intermediate to the holotypic ss and sl morphologies. We find no systematic or significant offsets in coeval ss-sl δ18O, and δ13C. These offsets are no larger than those in the intermediate pairs. Coupling our results with foraminiferal statistical model INFAUNAL, we find that contrary to previous work elsewhere, there is no evidence for discrepancies in ss-sl calcifying depth habitat or seasonality in the Gulf of Mexico.

Don't abandon hope all ye who enter here: The protective role of formal mentoring and learning processes on burnout in correctional officers.

PubMed

Farnese, M L; Barbieri, B; Bellò, B; Bartone, P T

2017-01-01

Within a Job Demands-Resources Model framework, formal mentoring can be conceived as a job resource expressing the organization's support for new members, which may prevent their being at risk for burnout. This research aims at understanding the protective role of formal mentoring on burnout, through the effect of increasing learning personal resources. Specifically, we hypothesized that formal mentoring enhances newcomers' learning about job and social domains related to the new work context, thus leading to lower burnout. In order to test the hypotheses, a multiple regression analysis using the bootstrapping method was used. Based on a questionnaire administered to 117 correctional officer newcomers who had a formal mentor assigned, our results confirm that formal mentoring exerts a positive influence on newcomers' adjustment, and that this in turn exerts a protective influence against burnout onset by reducing cynicism and interpersonal stress and also enhancing the sense of personal accomplishment. Confirming previous literature's suggestions, supportive mentoring and effective socialization seem to represent job and personal resources that are protective against burnout. This study provides empirical support for this relation in the prison context.

Understanding the Cognitive and Genetic Underpinnings of Procrastination: Evidence for Shared Genetic Influences with Goal Management and Executive Function Abilities

PubMed Central

Gustavson, Daniel E.; Miyake, Akira; Hewitt, John K.; Friedman, Naomi P.

2015-01-01

Previous research has suggested that individual differences in procrastination are tied to everyday goal-management abilities, but little research has been conducted on specific cognitive abilities that may underlie tendencies for procrastination, such as executive functions (EFs). In this study, we used behavioral genetics methodology to investigate two hypotheses about the relationships between procrastination and EF ability: (a) that procrastination is negatively correlated with general EF ability, and (b) that this relationship is due to the genetic components of procrastination that are most related to other everyday goal-management abilities. The results confirmed both of these hypotheses. Procrastination was related to worse general EF ability at both the phenotypic and genetic levels, and this relationship was due to the component of procrastination shared with self-report measures of everyday goal-management failures. These results were observed even after controlling for potential self-report biases stemming from the urge to respond in a socially desirable manner. Together, these findings provide strong evidence for growing theories of procrastination emphasizing the importance of goal-related cognitive abilities and further highlight important genetic influences that underlie procrastination. PMID:26389573

Understanding the cognitive and genetic underpinnings of procrastination: Evidence for shared genetic influences with goal management and executive function abilities.

PubMed

Gustavson, Daniel E; Miyake, Akira; Hewitt, John K; Friedman, Naomi P

2015-12-01

Previous research has suggested that individual differences in procrastination are tied to everyday goal-management abilities, but little research has been conducted on specific cognitive abilities that may underlie tendencies for procrastination, such as executive functions (EFs). In this study, we used behavioral genetics methodology to investigate 2 hypotheses about the relationships between procrastination and EF ability: (a) that procrastination is negatively correlated with general EF ability, and (b) that this relationship is due to the genetic components of procrastination that are most related to other everyday goal-management abilities. The results confirmed both of these hypotheses. Procrastination was related to worse general EF ability at both the phenotypic and genetic levels, and this relationship was due to the component of procrastination shared with self-report measures of everyday goal-management failures. These results were observed even after controlling for potential self-report biases stemming from the urge to respond in a socially desirable manner. Together, these findings provide strong evidence for growing theories of procrastination emphasizing the importance of goal-related cognitive abilities and further highlight important genetic influences that underlie procrastination. (c) 2015 APA, all rights reserved).

Mechanism of the 5-hydroxytryptamine 2A receptor-mediated facilitation of synaptic activity in prefrontal cortex

PubMed Central

Béïque, Jean-Claude; Imad, Mays; Mladenovic, Ljiljana; Gingrich, Jay A.; Andrade, Rodrigo

2007-01-01

Classic hallucinogens such as lysergic acid diethylamide are thought to elicit their psychotropic actions via serotonin receptors of the 5-hydroxytryptamine 2A subtype (5-HT2AR). One likely site for these effects is the prefrontal cortex (PFC). Previous studies have shown that activation of 5-HT2ARs in this region results in a robust increase in spontaneous glutamatergic synaptic activity, and these results have led to the widely held idea that hallucinogens elicit their effect by modulating synaptic transmission within the PFC. Here, we combine cellular and molecular biological approaches, including single-cell 5-HT2ARs inactivation and 5-HT2AR rescue over a 5-HT2AR knockout genetic background, to distinguish between competing hypotheses accounting for these effects. The results from these experiments do not support the idea that 5-HT2ARs elicit the release of an excitatory retrograde messenger nor that they activate thalamocortical afferents, the two dominant hypotheses. Rather, they suggest that 5-HT2ARs facilitate intrinsic networks within the PFC. Consistent with this idea, we locate a discrete subpopulation of pyramidal cells that is strongly excited by 5-HT2AR activation. PMID:17535909

Inferring ‘weak spots’ in phylogenetic trees: application to mosasauroid nomenclature

PubMed Central

2017-01-01

Mosasauroid squamates represented the apex predators within the Late Cretaceous marine and occasionally also freshwater ecosystems. Proper understanding of the origin of their ecological adaptations or paleobiogeographic dispersals requires adequate knowledge of their phylogeny. The studies assessing the position of mosasauroids on the squamate evolutionary tree and their origins have long given conflicting results. The phylogenetic relationships within Mosasauroidea, however, have experienced only little changes throughout the last decades. Considering the substantial improvements in the development of phylogenetic methodology that have undergone in recent years, resulting, among others, in numerous alterations in the phylogenetic hypotheses of other fossil amniotes, we test the robustness in our understanding of mosasauroid beginnings and their evolutionary history. We re-examined a data set that results from modifications assembled in the course of the last 20 years and performed multiple parsimony analyses and Bayesian tip-dating analysis. Following the inferred topologies and the ‘weak spots’ in the phylogeny of mosasauroids, we revise the nomenclature of the ‘traditionally’ recognized mosasauroid clades, to acknowledge the overall weakness among branches and the alternative topologies suggested previously, and discuss several factors that might have an impact on the differing phylogenetic hypotheses and their statistical support. PMID:28929018

The neoteny-helper hypothesis: When to expect and when not to expect endocrine mechanisms to regulate allo-parental care?

PubMed

Schradin, Carsten; Vuarin, Pauline; Rimbach, Rebecca

2018-05-02

Family groups with helpers occur in several species of fish, birds and mammals. In such cooperatively breeding species all group members help with raising the offspring, i.e. parents and offspring from previous litters. While the ecological reasons and ultimate consequences of allo-parental care have been studied in detail, we know little about its physiological regulation. We propose three alternative hypotheses for the endocrine regulation of allo-parental care. 1. The neoteny-helper hypothesis predicts that helpers that did not undergo adolescence yet show helping behavior without any endocrine mechanisms activating it, as helping is the default response towards infant stimuli. The endocrine changes during adolescence would then deactivate helping behavior. 2. The parent-helper hypothesis predicts that helpers undergo the same endocrine changes as parents (increased prolactin and corticosterone levels; decreased testosterone in males but increased estrogen in females). We predict that this hypothesis is especially important in post-adolescent helpers. 3. The helper-specific hypothesis predicts that there are specific endocrine mechanisms that only exist in helpers but not in breeders. We review evidence for these three hypotheses in 23 species of fish, birds, and mammals. We found no evidence for the helper-specific hypothesis but for both other hypotheses. As predicted, this depended on whether helpers were pre- or post-adolescent, but information on whether or not helpers underwent adolescence was often missing. Thus, future studies should investigate whether or not helpers have reached sexual maturity, differentiate between pre- and post-adolescent helpers, and study behavioral changes in helping behavior during adolescence. We conclude that the neurobiological circuits in the brain necessary for allo-parental care might often be the default stage in helpers from cooperative breeding species, which might be deactivated by specific endocrine mechanisms during adolescence, and then would need reactivation for allo-parental and parental care. Copyright © 2017 Elsevier Inc. All rights reserved.

Acclimation and Institutionalization of the Mouse Microbiota Following Transportation

PubMed Central

Montonye, Dan R.; Ericsson, Aaron C.; Busi, Susheel B.; Lutz, Cathleen; Wardwell, Keegan; Franklin, Craig L.

2018-01-01

Using animal models, the gut microbiota has been shown to play a critical role in the health and disease of many organ systems. Unfortunately, animal model studies often lack reproducibility when performed at different institutions. Previous studies in our laboratory have shown that the gut microbiota of mice can vary with a number of husbandry factors leading us to speculate that differing environments may alter gut microbiota, which in turn may influence animal model phenotypes. As an extension of these studies, we hypothesized that the shipping of mice from a mouse producer to an institution will result in changes in the type, relative abundance, and functional composition of the gut microbiota. Furthermore, we hypothesized that mice will develop a microbiota unique to the institution and facility in which they are housed. To test these hypotheses, mice of two strains (C57BL/6J and BALB/cJ), two age groups (4 week and 8 week old), and originating from two types of housing (research animal facility under conventional housing and production facilities under maximum barrier housing) were obtained from The Jackson Laboratory. Fecal samples were collected the day prior to shipping, immediately upon arrival, and then on days 2, 5, 7, and weeks 2, 4, and 9 post-arrival. Following the first post-arrival fecal collection, mice were separated into 2 groups and housed at different facilities at our institution while keeping their caging, diet, and husbandry practices the same. DNA was extracted from the collected fecal pellets and 16S rRNA amplicons were sequenced in order to characterize the type and relative abundance of gut bacteria. Principal component analysis (PCA) and permutational multivariate analysis of variance (PERMANOVA) demonstrated that both the shipping and the institution and facility in which mice were housed altered the gut microbiota. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) predicted differences in functional composition in the gut microbiota of mice based on time of acclimation. PMID:29892276

Acclimation and Institutionalization of the Mouse Microbiota Following Transportation.

PubMed

Montonye, Dan R; Ericsson, Aaron C; Busi, Susheel B; Lutz, Cathleen; Wardwell, Keegan; Franklin, Craig L

2018-01-01

Using animal models, the gut microbiota has been shown to play a critical role in the health and disease of many organ systems. Unfortunately, animal model studies often lack reproducibility when performed at different institutions. Previous studies in our laboratory have shown that the gut microbiota of mice can vary with a number of husbandry factors leading us to speculate that differing environments may alter gut microbiota, which in turn may influence animal model phenotypes. As an extension of these studies, we hypothesized that the shipping of mice from a mouse producer to an institution will result in changes in the type, relative abundance, and functional composition of the gut microbiota. Furthermore, we hypothesized that mice will develop a microbiota unique to the institution and facility in which they are housed. To test these hypotheses, mice of two strains (C57BL/6J and BALB/cJ), two age groups (4 week and 8 week old), and originating from two types of housing (research animal facility under conventional housing and production facilities under maximum barrier housing) were obtained from The Jackson Laboratory. Fecal samples were collected the day prior to shipping, immediately upon arrival, and then on days 2, 5, 7, and weeks 2, 4, and 9 post-arrival. Following the first post-arrival fecal collection, mice were separated into 2 groups and housed at different facilities at our institution while keeping their caging, diet, and husbandry practices the same. DNA was extracted from the collected fecal pellets and 16S rRNA amplicons were sequenced in order to characterize the type and relative abundance of gut bacteria. Principal component analysis (PCA) and permutational multivariate analysis of variance (PERMANOVA) demonstrated that both the shipping and the institution and facility in which mice were housed altered the gut microbiota. Phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt) predicted differences in functional composition in the gut microbiota of mice based on time of acclimation.

Variability in avian eggshell colour: a comparative study of museum eggshells.

PubMed

Cassey, Phillip; Portugal, Steven J; Maurer, Golo; Ewen, John G; Boulton, Rebecca L; Hauber, Mark E; Blackburn, Tim M

2010-08-09

The exceptional diversity of coloration found in avian eggshells has long fascinated biologists and inspired a broad range of adaptive hypotheses to explain its evolution. Three main impediments to understanding the variability of eggshell appearance are: (1) the reliable quantification of the variation in eggshell colours; (2) its perception by birds themselves, and (3) its relation to avian phylogeny. Here we use an extensive museum collection to address these problems directly, and to test how diversity in eggshell coloration is distributed among different phylogenetic levels of the class Aves. Spectrophotometric data on eggshell coloration were collected from a taxonomically representative sample of 251 bird species to determine the change in reflectance across different wavelengths and the taxonomic level where the variation resides. As many hypotheses for the evolution of eggshell coloration assume that egg colours provide a communication signal for an avian receiver, we also modelled reflectance spectra of shell coloration for the avian visual system. We found that a majority of species have eggs with similar background colour (long wavelengths) but that striking differences are just as likely to occur between congeners as between members of different families. The region of greatest variability in eggshell colour among closely related species coincided with the medium-wavelength sensitive region around 500 nm. The majority of bird species share similar background eggshell colours, while the greatest variability among species aligns with differences along a red-brown to blue axis that most likely corresponds with variation in the presence and concentration of two tetrapyrrole pigments responsible for eggshell coloration. Additionally, our results confirm previous findings of temporal changes in museum collections, and this will be of particular concern for studies testing intraspecific hypotheses relating temporal patterns to adaptation of eggshell colour. We suggest that future studies investigating the phylogenetic association between the composition and concentration of eggshell pigments, and between the evolutionary drivers and functional impacts of eggshell colour variability will be most rewarding.

Leptin Regulation of Gonadotrope Gonadotropin-Releasing Hormone Receptors As a Metabolic Checkpoint and Gateway to Reproductive Competence

PubMed Central

Odle, Angela K.; Akhter, Noor; Syed, Mohsin M.; Allensworth-James, Melody L.; Beneš, Helen; Melgar Castillo, Andrea I.; MacNicol, Melanie C.; MacNicol, Angus M.; Childs, Gwen V.

2018-01-01

The adipokine leptin signals the body’s nutritional status to the brain, and particularly, the hypothalamus. However, leptin receptors (LEPRs) can be found all throughout the body and brain, including the pituitary. It is known that leptin is permissive for reproduction, and mice that cannot produce leptin (Lep/Lep) are infertile. Many studies have pinpointed leptin’s regulation of reproduction to the hypothalamus. However, LEPRs exist at all levels of the hypothalamic–pituitary–gonadal axis. We have previously shown that deleting the signaling portion of the LEPR specifically in gonadotropes impairs fertility in female mice. Our recent studies have targeted this regulation to the control of gonadotropin releasing hormone receptor (GnRHR) expression. The hypotheses presented here are twofold: (1) cyclic regulation of pituitary GnRHR levels sets up a target metabolic checkpoint for control of the reproductive axis and (2) multiple checkpoints are required for the metabolic signaling that regulates the reproductive axis. Here, we emphasize and explore the relationship between the hypothalamus and the pituitary with regard to the regulation of GnRHR. The original data we present strengthen these hypotheses and build on our previous studies. We show that we can cause infertility in 70% of female mice by deleting all isoforms of LEPR specifically in gonadotropes. Our findings implicate activin subunit (InhBa) mRNA as a potential leptin target in gonadotropes. We further show gonadotrope-specific upregulation of GnRHR protein (but not mRNA levels) following leptin stimulation. In order to try and understand this post-transcriptional regulation, we tested candidate miRNAs (identified with in silico analysis) that may be binding the Gnrhr mRNA. We show significant upregulation of one of these miRNAs in our gonadotrope-Lepr-null females. The evidence provided here, combined with our previous work, lay the foundation for metabolically regulated post-transcriptional control of the gonadotrope. We discuss possible mechanisms, including miRNA regulation and the involvement of the RNA binding protein, Musashi. We also demonstrate how this regulation may be vital for the dynamic remodeling of gonadotropes in the cycling female. Finally, we propose that the leptin receptivity of both the hypothalamus and the pituitary are vital for the body’s ability to delay or slow reproduction during periods of low nutrition. PMID:29354094

The inaction effect in the psychology of regret.

PubMed

Zeelenberg, Marcel; van de Bos, Kees; van Dijk, Eric; Pieters, Rik

2002-03-01

Previous research showed that decisions to act (i.e., actions) produce more regret than decisions not to act (i.e., inactions). This previous research focused on decisions made in isolation and ignored that decisions are often made in response to earlier outcomes. The authors show in 4 experiments that these prior outcomes may promote action and hence make inaction more abnormal. They manipulated information about a prior outcome. As hypothesized, when prior outcomes were positive or absent, people attributed more regret to action than to inaction. However, as predicted and counter to previous research, following negative prior outcomes, more regret was attributed to inaction, a finding that the authors label the inaction effect. Experiment 4, showing differential effects for regret and disappointment, demonstrates the need for emotion-specific predictions.

A novel approach to generating CER hypotheses based on mining clinical data.

PubMed

Zhang, Shuo; Li, Lin; Yu, Yiqin; Sun, Xingzhi; Xu, Linhao; Zhao, Wei; Teng, Xiaofei; Pan, Yue

2013-01-01

Comparative effectiveness research (CER) is a scientific method of investigating the effectiveness of alternative intervention methods. In a CER study, clinical researchers typically start with a CER hypothesis, and aim to evaluate it by applying a series of medical statistical methods. Traditionally, the CER hypotheses are defined manually by clinical researchers. This makes the task of hypothesis generation very time-consuming and the quality of hypothesis heavily dependent on the researchers' skills. Recently, with more electronic medical data being collected, it is highly promising to apply the computerized method for discovering CER hypotheses from clinical data sets. In this poster, we proposes a novel approach to automatically generating CER hypotheses based on mining clinical data, and presents a case study showing that the approach can facilitate clinical researchers to identify potentially valuable hypotheses and eventually define high quality CER studies.

Episode-specific drinking-to-cope motivation, daily mood, and fatigue-related symptoms among college students.

PubMed

Armeli, Stephen; O'Hara, Ross E; Ehrenberg, Ethan; Sullivan, Tami P; Tennen, Howard

2014-09-01

The goal of the present study was to examine whether within-person, episode-specific changes in drinking-to-cope (DTC) motivation from the previous evening were associated with concurrent daily mood and fatigue-related symptoms among college student drinkers (N = 1,421; 54% female). We conducted an Internet-based daily diary study in which students reported over 30 days on their previous night's drinking level and motivation and their current mood (i.e., sadness, anxiety, anger/hostility, and positive mood) and fatigue-related symptoms. Hypotheses were tested using hierarchical linear models in which the current day's outcome was predicted by last night's levels of DTC motivation and drinking, controlling for drinking to enhance motivation, sex, current day's physical symptoms and drinking, and yesterday's level of the outcome. Subsequent models also predicted outcomes 2 days following the drinking event. Relative increases in previous night's DTC motivation were associated with higher levels of current day negative mood and fatigue-related symptoms and lower levels of positive mood. Also, the association between episode-specific DTC motivation and negative mood was stronger in the positive direction when individuals reported higher levels of nonsocial drinking from the previous night. Last, episode-specific DTC showed similar associations with sadness and anger/hostility 2 days after the drinking event. The results are generally consistent with the posited attention allocation and ego-depletion mechanisms. Findings suggest that the deleterious effects of repeated episodes of DTC, over time, could help to explain the increased likelihood of alcohol-related problems seen in prior studies.

Sitagliptin on carotid intima-media thickness in type 2 diabetes patients receiving primary or secondary prevention of cardiovascular disease: A subgroup analysis of the PROLOGUE study.

PubMed

Tanaka, Atsushi; Yoshida, Hisako; Nanasato, Mamoru; Oyama, Jun-Ichi; Ishizu, Tomoko; Ajioka, Masayoshi; Ishiki, Ryoji; Saito, Makoto; Shibata, Yoshisato; Kaku, Kohei; Maemura, Koji; Higashi, Yukihito; Inoue, Teruo; Murohara, Toyoaki; Node, Koichi

2018-05-19

Whether a dipeptidyl peptidase-4 (DPP-4) inhibitor can attenuate atherosclerosis is still controversial. Some clinical trials reported that DPP-4 inhibitors in diabetes patients without a previous history of cardiovascular (CV) events could reduce carotid intima-media thickness (IMT). However, in the PROLOGUE study, which enrolled diabetes patients both with and without previous CV events, sitagliptin failed to slow the progression of carotid IMT relative to conventional therapy. We hypothesized that the effect of DPP-4 inhibitors on carotid atherosclerosis might be different between the primary and secondary prevention groups. We performed a post hoc analysis of the PROLOGUE study and compared the effects of sitagliptin and conventional therapy on changes in carotid IMT in subgroups with or without previous CV events. No significant difference in the IMT changes between the treatment groups was found in the secondary prevention subgroup (sitagliptin, N = 102; conventional, 111). However, in the primary prevention subgroup (sitagliptin, 120; conventional, 109), we found significant inhibitory effects of sitagliptin on mean and max internal carotid artery IMT [estimated group difference: -0.096 mm (95% CI -0.175 to -0.018, p = 0.017) and -0.162 mm (95% CI -0.272 to -0.052, p = 0.004), respectively], although there was no significant difference in the common carotid artery IMT. Our data suggest that there is a favorable effect of DPP-4 inhibitor treatment on carotid atherosclerosis in diabetes patients without previous CV events. Copyright © 2017 Elsevier B.V. All rights reserved.

The structure of the UPPS-R-Child impulsivity scale and its relations with substance use outcomes among treatment-seeking adolescents.

PubMed

Tomko, Rachel L; Prisciandaro, James J; Falls, Sandhya Kutty; Magid, Viktoriya

2016-04-01

A youth version of the UPPS Impulsivity Scale (UPPS-R-C) was previously shown to predict drinking initiation among pre-adolescents. The goals of the current study were to confirm the structure of the UPPS-R-C using a sample of treatment-seeking adolescents and to examine the scales' relations with alcohol use, marijuana use, and problems related to substance use. Participants (N=120; ages 12-18; M=15.7) completed questionnaires at treatment intake. Confirmatory factor analysis (CFA) of the UPPS-R-C was conducted using a 5-factor model with factors corresponding to negative urgency, positive urgency, lack of perseverance, lack of premeditation, and sensation seeking. Relations between UPPS-R-C factors and binge drinking, marijuana use, and problems resulting from substance use were examined using path analysis. CFA suggested the 5-factor model provided adequate fit to the data. The hypothesized path model was partially supported, positive urgency was associated with frequency of binge drinking, and both negative urgency and frequency of binge drinking was associated with problems due to substance use. Other hypothesized paths were not significant. Although not hypothesized, negative urgency was associated with frequency of marijuana use and lack of perseverance was associated with problems due to use. Results suggest that the UPPS-R-C can be used with a treatment-seeking sample of adolescents. Furthermore, negative urgency, positive urgency, and lack of perseverance may be indicative of more severe substance use problems in a treatment setting. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

The Structure of the UPPS-R-Child Impulsivity Scale and its Relations with Substance Use Outcomes Among Treatment-Seeking Adolescents

PubMed Central

Prisciandaro, James J.; Kutty Falls, Sandhya; Magid, Viktoriya

2016-01-01

Background A youth version of the UPPS Impulsivity Scale (UPPS-R-C) was previously shown to predict drinking initiation among pre-adolescents. The goals of the current study were to confirm the structure of the UPPS-R-C using a sample of treatment-seeking adolescents and to examine the scales’ relations with alcohol use, marijuana use, and problems related to substance use. Method Participants (N = 120; ages 12–18; M = 15.7) completed questionnaires at treatment intake. Confirmatory factor analysis (CFA) of the UPPS-R-C was conducted using a 5-factor model with factors corresponding to negative urgency, positive urgency, lack of perseverance, lack of premeditation, and sensation seeking. Relations between UPPS-R-C factors and binge drinking, marijuana use, and problems resulting from substance use were examined using path analysis. Results CFA suggested the 5-factor model provided adequate fit to the data. The hypothesized path model was partially supported, positive urgency was associated with frequency of binge drinking, and both negative urgency and frequency of binge drinking was associated with problems due to substance use. Other hypothesized paths were not significant. Although not hypothesized, negative urgency was associated with frequency of marijuana use and lack of perseverance was associated with problems due to use. Conclusions Results suggest that the UPPS-R-C can be used with a treatment-seeking sample of adolescents. Furthermore, negative urgency, positive urgency, and lack of perseverance may be indicative of more severe substance use problems in a treatment setting. PMID:26905208

Factors affecting summer distributions of Bering Sea forage fish species: Assessing competing hypotheses

NASA Astrophysics Data System (ADS)

Parker-Stetter, Sandra; Urmy, Samuel; Horne, John; Eisner, Lisa; Farley, Edward

2016-12-01

Hypotheses on the factors affecting forage fish species distributions are often proposed but rarely evaluated using a comprehensive suite of indices. Using 24 predictor indices, we compared competing hypotheses and calculated average models for the distributions of capelin, age-0 Pacific cod, and age-0 pollock in the eastern Bering Sea from 2006 to 2010. Distribution was described using a two stage modeling approach: probability of occurrence ("presence") and density when fish were present. Both local (varying by location and year) and annual (uniform in space but varying by year) indices were evaluated, the latter accounting for the possibility that distributions were random but that overall presence or densities changed with annual conditions. One regional index, distance to the location of preflexion larvae earlier in the year, was evaluated for age-0 pollock. Capelin distributions were best predicted by local indices such as bottom depth, temperature, and salinity. Annual climate (May sea surface temperature (SST), sea ice extent anomaly) and wind (June wind speed cubed) indices were often important for age-0 Pacific cod in addition to local indices (temperature and depth). Surface, midwater, and water column age-0 pollock distributions were best described by a combination of local (depth, temperature, salinity, zooplankton) and annual (May SST, sea ice anomaly, June wind speed cubed) indices. Our results corroborated some of those in previous distribution studies, but suggested that presence and density may also be influenced by other factors. Even though there were common environmental factors that influenced all species' distributions, it is not possible to generalize conditions for forage fish as a group.

A chronometric exploration of high-resolution 'sensitive TMS masking' effects on subjective and objective measures of vision.

PubMed

de Graaf, Tom A; Herring, Jim; Sack, Alexander T

2011-03-01

Transcranial magnetic stimulation (TMS) can induce masking by interfering with ongoing neural activity in early visual cortex. Previous work has explored the chronometry of occipital involvement in vision by using single pulses of TMS with high temporal resolution. However, conventionally TMS intensities have been high and the only measure used to evaluate masking was objective in nature. Recent studies have begun to incorporate subjective measures of vision, alongside objective ones. The current study goes beyond previous work in two regards. First, we explored both objective vision (an orientation discrimination task) and subjective vision (a stimulus visibility rating on a four-point scale), across a wide range of time windows with high temporal resolution. Second, we used a very sensitive TMS-masking paradigm: stimulation was at relatively low TMS intensities, with a figure-8 coil, and the small stimulus was difficult to discriminate already at baseline level. We hypothesized that this should increase the effective temporal resolution of our paradigm. Perhaps for this reason, we are able to report a rather interesting masking curve. Within the classical-masking time window, previously reported to encompass broad SOAs anywhere between 60 and 120 ms, we report not one, but at least two dips in objective performance, with no masking in-between. The subjective measure of vision did not mirror this pattern. These preliminary data from our exploratory design suggest that, with sensitive TMS masking, we might be able to reveal visual processes in early visual cortex previously unreported.

Correlating chemical sensitivity and basal gene expression reveals mechanism of action | Office of Cancer Genomics

Cancer.gov

Changes in cellular gene expression in response to small-molecule or genetic perturbations have yielded signatures that can connect unknown mechanisms of action (MoA) to ones previously established. We hypothesized that differential basal gene expression could be correlated with patterns of small-molecule sensitivity across many cell lines to illuminate the actions of compounds whose MoA are unknown.

The Effects of Childhood Exposure to Drug Users and Religion on Drug Use in Adolescence and Young Adulthood

ERIC Educational Resources Information Center

Jang, Sung Joon; Johnson, Byron R.

2011-01-01

Previous research finds drug-using peers and religiosity to be key predictors of drug use among youth, but the effects of childhood exposure to drug users and religion on later drug use have been understudied. The authors hypothesize a child's exposure to parental drug use and religious upbringing have a causal influence on drug use in youth…

Toward a Typology of Abusive Women: Differences between Partner-Only and Generally Violent Women in the Use of Violence

ERIC Educational Resources Information Center

Babcock, Julia C.; Miller, Sarah A.; Siard, Cheryl

2003-01-01

Based on previous typologies of domestically violent men (Holtzworth-Munroe & Stuart, 1994), women who were referred to a treatment agency for abusive behavior (N = 52) were categorized into two groups based on the breadth of their use of violence: Partner-Only (PO) and Generally Violent (GV). PO women were hypothesized to use reactive violence,…

The STRONG STAR Multidisciplinary PTSD Research Consortium

DTIC Science & Technology

2009-09-01

superior A.5 Role of the Serotonin Transporter and Serotonergic Hypotheses related to Alcoholism Vulnerability Due to Low Serotonin. Strong...evidence shows that the biological vulnerability of EOA patients may be related to a serotonergic dysfunction (Johnson, 2000; Johnson and Ait-Daoud...transporter (Johnson et al., 2008). These findings of reduced serotonergic functioning in L-carriers is contrary to previous data indicating that the L

The Role of SDF-1alpha and CXCR4 in Metastatic Breast Cancer

DTIC Science & Technology

2006-08-01

vegetables of the genus Brassica can inhibit NF-κB in breast cancer cells. Therefore, we hypothesize that I3C may be able to inhibit the bone metastasis...and NF-κB. We have previously shown that Indole-3-carbinol (I3C), a natural compound present in vegetables of the genus Brassica , can inhibit NF-κB

Translational Control in Bone Marrow Failure

DTIC Science & Technology

2015-05-01

HCLS1 associated protein X-1 (HAX1), cause hereditary forms of neutropenia . Previously, competing hypotheses have posited that mutant forms of...derived induced pluripotent stem cell (iPSC) model of ELANE-associated neutropenia . During the second year of this project, in order to facilitate...pathology. 3 2. KEY WORDS neutropenia bone marrow failure neutrophil elastase ELANE HAX1 alternate translation induced pluripotent stem cells (iPSC

Experimental study on the role of the ankle push off in the walk-to-run transition by means of a powered ankle-foot-exoskeleton.

PubMed

Malcolm, P; Fiers, P; Segers, V; Van Caekenberghe, I; Lenoir, M; De Clercq, D

2009-10-01

The goal of this study was to analyse the role of the plantarflexor muscles in the walk-to-run transition (WRT) by means of a powered ankle-foot-exoskeleton. 11 female subjects performed several WRT's on an accelerating treadmill while their plantarflexors were assisted or resisted during push off. The WRT speed was lower in the resist condition than in the control condition which reinforces hypotheses from previous simulations, descriptive and experimental studies. There was no increase in WRT speed in the assist condition which is in contrast to another study where the plantarflexor push off was assisted indirectly by a horizontal traction at waist level. The lack of effect from the assist condition in the present study is possibly due to the narrowly focused nature of the experimental manipulation.

The picture superiority effect: support for the distinctiveness model.

PubMed

Mintzer, M Z; Snodgrass, J G

1999-01-01

The form change paradigm was used to explore the basis for the picture superiority effect. Recognition memory for studied pictures and words was tested in their study form or the alternate form. Form change cost was defined as the difference between recognition performance for same and different form items. Based on the results of Experiment 1 and previous studies, it was difficult to determine the relative cost for studied pictures and words due to a reversal of the mirror effect. We hypothesized that the reversed mirror effect results from subjects' basing their recognition decisions on their assumptions about the study form. Experiments 2 and 3 confirmed this hypothesis and generated a method for evaluating the relative cost for pictures and words despite the reversed mirror effect. More cost was observed for pictures than words, supporting the distinctiveness model of the picture superiority effect.

Bone Proteoglycan Changes During Skeletal Unloading

NASA Technical Reports Server (NTRS)

Yamauchi, M.; Uzawa, K.; Pornprasertsuk, S.; Arnaud, S.; Grindeland, R.; Grzesik, W.

1999-01-01

Skeletal adaptability to mechanical loads is well known since the last century. Disuse osteopenia due to the microgravity environment is one of the major concerns for space travelers. Several studies have indicated that a retardation of the mineralization process and a delay in matrix maturation occur during the space flight. Mineralizing fibrillar type I collagen possesses distinct cross-linking chemistries and their dynamic changes during mineralization correlate well with its function as a mineral organizer. Our previous studies suggested that a certain group of matrix proteoglycans in bone play an inhibitory role in the mineralization process through their interaction with collagen. Based on these studies, we hypothesized that the altered mineralization during spaceflight is due in part to changes in matrix components secreted by cells in response to microgravity. In this study, we employed hindlimb elevation (tail suspension) rat model to study the effects of skeletal unloading on matrix proteoglycans in bone.

Drosophila VAMP7 regulates Wingless intracellular trafficking.

PubMed

Gao, Han; He, Fang; Lin, Xinhua; Wu, Yihui

2017-01-01

Drosophila Wingless (Wg) is a morphogen that determines cell fate during development. Previous studies have shown that endocytic pathways regulate Wg trafficking and signaling. Here, we showed that loss of vamp7, a gene required for vesicle fusion, dramatically increased Wg levels and decreased Wg signaling. Interestingly, we found that levels of Dally-like (Dlp), a glypican that can interact with Wg to suppress Wg signaling at the dorsoventral boundary of the Drosophila wing, were also increased in vamp7 mutant cells. Moreover, Wg puncta in Rab4-dependent recycling endosomes were Dlp positive. We hypothesize that VAMP7 is required for Wg intracellular trafficking and the accumulation of Wg in Rab4-dependent recycling endosomes might affect Wg signaling.

Thinking of You: Nonconscious Pursuit of Interpersonal Goals Associated With Relationship Partners

PubMed Central

Fitzsimons, Gráinne M.; Bargh, John A.

2010-01-01

The mere psychological presence of relationship partners was hypothesized to trigger interpersonal goals that are then pursued nonconsciously. Qualitative data suggested that people tend to pursue different interpersonal goals within different types of relationships (e.g., mother, best friend, coworker). In several studies, priming participants’ relationship representations produced goal-directed behavior (achievement, helping, understanding) in line with the previously assessed goal content of those representations. These findings support the hypothesis that interpersonal goals are component features of relationship representations and that mere activation of those representations, even in the partner’s physical absence, causes the goals to become active and to guide behavior nonconsciously within the current situation. PMID:12518976

Fathers, sons, and sexual orientation: replication of a Bieber hypothesis.

PubMed

Friedman, R C; Stern, L O

1980-01-01

This retrospective study compares memories of the father-son relationship between lifelong socially well-adjusted, non-patient homosexual and heterosexual men. No homosexual subject reported the presence of a reasonably intact, positive relationship with his father or father surrogate during preadolescent years, whereas 12 of the 17 heterosexual men did. Previous investigators have hypothesized that a constructive, supportive father-son relationship precludes the development of homosexual orientation. This hypothesis stemmed from investigation of men who in general suffered from significant global psychopathology. The data in the present investigation supports the notion that a meaningful association, which is not attributable to confounding psychopathology, exists between quality of father-son relationship during early life and male sexual orientation.

Genes from scratch--the evolutionary fate of de novo genes.

PubMed

Schlötterer, Christian

2015-04-01

Although considered an extremely unlikely event, many genes emerge from previously noncoding genomic regions. This review covers the entire life cycle of such de novo genes. Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks. Further studies combining gene expression with ribosome profiling in multiple populations across different species will be instrumental for an improved understanding of the evolutionary processes operating on de novo genes. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

Flavonoid transport mechanisms: how to go, and with whom.

PubMed

Zhao, Jian

2015-09-01

Subcellular flavonoid transport and its underlying regulatory mechanisms are still poorly understood, but are fascinating research frontiers in plant science. Recent studies support and further extend previous hypotheses indicating that vacuolar sequestration of flavonoids involves vesicle trafficking, membrane transporters, and glutathione S-transferase (GST). However, the question remains to be addressed of how three distinct but nonexclusive mechanisms are functionally integrated into diverse but redundant transport routes for vacuolar sequestration or extracellular secretion of flavonoids. In this review, I highlight recent progress in understanding flavonoid-transporting vesicle behavior and properties, GST and membrane transporter functions and mechanisms, and flavonoid transport substrate specificity and preference. Copyright © 2015 Elsevier Ltd. All rights reserved.

The mediating role of self-efficacy in the development of entrepreneurial intentions.

PubMed

Zhao, Hao; Seibert, Scott E; Hills, Gerald E

2005-11-01

The purpose of this study was to investigate the mediating role of self-efficacy in the development of students' intentions to become entrepreneurs. The authors used structural equation modeling with a sample of 265 master of business administration students across 5 universities to test their hypotheses. The results showed that the effects of perceived learning from entrepreneurship-related courses, previous entrepreneurial experience, and risk propensity on entrepreneurial intentions were fully mediated by entrepreneurial self-efficacy. Contrary to expectations, gender was not mediated by self-efficacy but had a direct effect such that women reported lower entrepreneurial career intentions. The authors discuss practical implications and directions for future research. ((c) 2005 APA, all rights reserved).

Pilot study on the effects of a computer-based medical image system.

PubMed Central

Wu, S. C.; Smith, J. W.; Swan, J. E.

1996-01-01

Current medical imaging systems are developed for the purpose of data management. Evaluations of these systems are usually done by assessing users' subjective appreciation rather than objectively gauging performance influence. The present report discusses the evaluation of a medical image presentation system prototype utilizing a cognitive approach. Experimental results showed hypothesized performance improvement attributed to advanced presentation techniques. However, this improvement was almost inadvertently masked by users' previous strategies and interactions with new technology. Overall these data demonstrate the potential benefit of implementing such a system in actual practice as well as provide an example of applying the cognitive approach in evaluating the usability of medical systems. Images Figure 1 PMID:8947750

The neural bases of the effects of item-nonspecific proactive interference in working memory

PubMed Central

POSTLE, BRADLEY R.; BRUSH, LAUREN N.

2005-01-01

We reanalyzed the behavioral and fMRI data from seven previously published studies of working memory in order to assess the behavioral and neural effects of item-nonspecific proactive interference (PI; attributable to the accrual of antecedent information independent of the repetition of particular items). We hypothesized that item-nonspecific PI, implicated in age-related declines in working memory performance, is mediated by the same mechanism(s) that mediate item-specific PI (occurring when an invalid memory probe matches a memorandum from the previous trial). Reaction time increased across trials as a function of position within the block, a trend that reversed across the duration of each multiblock experiment. The fMRI analyses revealed sensitivity to item-nonspecific PI during the probe epoch in the left anterior inferior frontal gyrus and the left dorsolateral prefrontal cortex (PFC). They also revealed a negative trend, across trials, in the transient probe-evoked component of the global signal. A common PFC-based mechanism may mediate many forms of PI. PMID:15535173

The neural bases of the effects of item-nonspecific proactive interference in working memory.

PubMed

Postle, Bradley R; Brush, Lauren N

2004-09-01

We reanalyzed the behavioral and fMRI data from seven previously published studies of working memory in order to assess the behavioral and neural effects of item-nonspecific proactive interference (PI; attributable to the accrual of antecedent information independent of the repetition of particular items). We hypothesized that item-nonspecific PI, implicated in age-related declines in working memory performance, is mediated by the same mechanism(s) that mediate item-specific PI (occurring when an invalid memory probe matches a memorandum from the previous trial). Reaction time increased across trials as a function of position within the block, a trend that reversed across the duration of each multiblock experiment. The fMRI analyses revealed sensitivity to item-nonspecific PI during the probe epoch in the left anterior inferior frontal gyrus and the left dorsolateral prefrontal cortex(PFC). They also revealed a negative trend, across trials, in the transient probe-evoked component of the global signal. A common PFC-based mechanism may mediate many forms of PI.

Racial-Ethnic Protective Factors and Mechanisms in Psychosocial Prevention and Intervention Programs for Black Youth.

PubMed

Jones, Shawn C T; Neblett, Enrique W

2016-06-01

Extending previous reviews related to cultural responsiveness in the treatment of ethnic minority youth, the current review provides a critical assessment and synthesis of both basic and applied research on the integration of three racial-ethnic protective factors (racial identity, racial socialization, Africentric worldview) in psychosocial prevention and intervention programs for Black children and adolescents. Seventeen programs meeting inclusion and exclusion criteria were evaluated for the extent to which racial-ethnic protective factors and related mechanisms were integrated, applied, and tested in such programs. A systematic assessment of these programs revealed that several prevention and intervention programs drew upon the three factors, particularly Africentric worldview. In addition, a number of studies hypothesized and assessed mechanisms, both those previously identified in conceptual literature and those that emerged from the interventions themselves. A set of recommendations encouraging the implementation of these factors into future prevention and intervention programs, examples of how clinicians can infuse these factors into psychotherapy, and areas for future research are discussed.

Discovery of missing link between demosponges and hexactinellids confirms palaeontological model of sponge evolution.

PubMed

Botting, Joseph P; Zhang, Yuandong; Muir, Lucy A

2017-07-13

The two major extant groups of siliceous sponges, Demospongiae and Hexactinellida, are generally regarded as sister groups forming the clade Silicea, although the nature of their last common ancestor is uncertain. The fossil record contains a diverse range of basal demosponges that appear to have evolved from hexactine-bearing reticulosan ancestors, although a compelling morphological intermediate has not previously been discovered. Here we describe a new species of fossil sponge, Conciliospongia anjiensis gen. et sp. nov., from the Late Ordovician (~444 Ma) Anji Biota of South China. This species has a reticulate, tufted skeleton of minute monaxon spicules, characteristic of the fossil demosponge family Hazeliidae and modern heteroscleromorphs, with hexactine spicules and a globose body form inherited from reticulosan ancestors. This transitional morphology had previously been hypothesized in palaeontological studies. This morphological intermediate between two extant classes further confirms siliceous sponge monophyly and demosponge-hexactinellid spicule homology, and supports the primitive, stem-silicean interpretation of simpler-structured fossil reticulosans.

Second-order many-body perturbation study of ice Ih

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

He, Xiao; Sode, Olaseni; Xantheas, Sotiris S.

2012-11-28

Ice Ih is arguably the most important molecular crystal in nature, yet our understanding of its structural and dynamical properties is still incomplete. To explain the origin of two peaks in the hydrogen-bond-stretching region of the inelastic neutron scattering (INS) spectra, the existence of two types of hydrogen bonds with strengths differing by a factor of two was previously hypothesized. We present first-principles calculations based on diagrammatic many-body perturbation theory of the structures and vibrational spectra of ice Ih, which suggest that the observed spectral features arise from the directionality or anisotropy of the hydrogen-bond stretching vibrations rather than theirmore » vastly different force constants, disproving the previous hypothesis. Our calculations also reproduce the infrared and Raman spectra, the variation of INS spectra with deuterium concentration, and the anomaly of heat capacities at low temperatures, together rendering our calculations a paradigm for "crystals from first principles" as envisioned by Maddox.« less

Does Social Support Mediate the Moderating Effect of Intrinsic Religiosity on the Relationship between Physical Health and Depressive Symptoms Among Jews?

PubMed Central

Pirutinsky, Steven; Rosmarin, David H.; Holt, Cheryl L.; Feldman, Robert H.; Caplan, Lee S.; Midlarsky, Elizabeth; Pargament, Kenneth I.

2018-01-01

Previous research in the general population suggests that intrinsic religiosity moderates (mitigates) the effect of poor physical health on depression. However, few studies have focused specifically on the Jewish community. We therefore examined these variables in a cross-sectional sample of 89 Orthodox and 123 non-Orthodox Jews. Based on previous research suggesting that non-Orthodox Judaism values religious mental states (e.g., beliefs) less and a collectivist social religiosity more, as compared to Orthodox Judaism, we hypothesized that the moderating effect of intrinsic religiosity would mediated by social support among non-Orthodox but not Orthodox Jews. As predicted, results indicated that the relationship between physical health and depression was moderated by intrinsic religiosity in the sample as a whole. Furthermore, this effect was mediated by social support among non-Orthodox Jews, but not among the Orthodox. The importance of examining religious affiliation and potential mediators in research on spirituality and health is discussed. PMID:21308407

Prefrontal glucose deficits in murderers lacking psychosocial deprivation.

PubMed

Raine, A; Phil, D; Stoddard, J; Bihrle, S; Buchsbaum, M

1998-01-01

Previous research has suggested that links between autonomic nervous system functioning and violence are strongest in those who come from benign home backgrounds, but there appears to be no similar research using brain-imaging measures of central nervous system functioning. It was hypothesized that murderers who had no early psychosocial deprivation (e.g., no childhood abuse, family neglect) would demonstrate lower prefrontal glucose metabolism than murderers with early psychosocial deprivation and a group of normal controls. Murderers from a previous study, which showed prefrontal deficits in murderers, were assessed for psychosocial deprivation and divided into those with and without deprivation. Murderers without any clear psychosocial deficits were significantly lower on prefrontal glucose metabolism than murderers with psychosocial deficits and controls. These results suggest that murderers lacking psychosocial deficits are characterized by prefrontal deficits. It is argued that among violent offenders without deprived home backgrounds, the "social push" to violence is minimized, and consequently, brain abnormalities provide a relatively stronger predisposition to violence in this group.

High basal metabolic rate does not elevate oxidative stress during reproduction in laboratory mice.

PubMed

Brzęk, Paweł; Książek, Aneta; Ołdakowski, Łukasz; Konarzewski, Marek

2014-05-01

Increased oxidative stress (OS) has been suggested as a physiological cost of reproduction. However, previous studies reported ambiguous results, with some even showing a reduction of oxidative damage during reproduction. We tested whether the link between reproduction and OS is mediated by basal metabolic rate (BMR), which has been hypothesized to affect both the rate of radical oxygen species production and antioxidative capacity. We studied the effect of reproduction on OS in females of laboratory mice divergently selected for high (H-BMR) and low (L-BMR) BMR, previously shown to differ with respect to parental investment. Non-reproducing L-BMR females showed higher oxidative damage to lipids (quantified as the level of malondialdehyde in internal organ tissues) and DNA (quantified as the level of 8-oxodG in blood serum) than H-BMR females. Reproduction did not affect oxidative damage to lipids in either line; however, it reduced damage to DNA in L-BMR females. Reproduction increased catalase activity in liver (significantly stronger in L-BMR females) and decreased it in kidneys. We conclude that the effect of reproduction on OS depends on the initial variation in BMR and varies between studied internal organs and markers of OS.

Sturgeon and paddlefish (Acipenseridae) saggital otoliths are composed of the calcium carbonate polymorphs vaterite and calcite: acipenseridae otoliths are vaterite and calcite

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

Pracheil, Brenda M.; Chakoumakos, Bryan C.; Feygenson, Mikhail

The otoliths of modern fishes are most commonly comprised of the metastable aragonite polymorph of calcium carbonate (CaCO3); however, sturgeons have otoliths reportedly comprised of the least stable of the three most-common polymorphs, vaterite. In this study, we used neutron diffraction to characterize CaCO3 polymorph composition of lake sturgeon and paddlefish otoliths. Based on previous summaries of CaCO3 composition over fish evolutionary history, we hypothesized that sturgeon and paddlefish otoliths would have similar polymorph composition. We found that despite previous reports of sturgeon otoliths being comprised entirely of vaterite, that all otoliths we examined in this study also had amore » calcite fraction that ranged from 17.9+ 6.0 wt. % to 35.9 + 2.9 wt. %. We also conducted a grinding experiment that demonstrated that calcite fractions were due to biological variation and not an artifact of polymorph transformation during preparation. Our study provides the initial characterization of the polymorph composition of the otoliths of lake sturgeon, and paddlefish and also provides the first-ever report of otoliths of Acipenserids as having a calcite fraction.« less

Morphospaces of functionally analogous traits show ecological separation between birds and pterosaurs.

PubMed

Chan, Nicholas R

2017-10-25

Birds originated and radiated in the presence of another group of flying vertebrates, the pterosaurs. Opinion is divided as to whether birds competitively displaced pterosaurs from small-body size niches or whether the two groups coexisted with little competition. Previous studies of Mesozoic birds and pterosaurs compared measurements of homologous limb bones to test these hypotheses. However, these characters probably reflect differing ancestries rather than ecologies. Here, competition and ecological separation were tested for using multivariate analyses of functionally equivalent morphological characters. As well as using characters from the fore- and hindlimbs, these analyses also included measurements of the lower jaw. The results of this study indicate that pterosaurs had relatively longer jaws, shorter metatarsals and shorter brachial regions compared with birds of similar size. Contrary to the results of previous studies, the distal wing was not important for separating the two clades in morphospace owing to the inclusion of the primary feathers in this unit. The differences found here indicate ecological separation based on differences in size, locomotory features and feeding adaptations. Thus, instead of one group displacing the other, birds and pterosaurs appear to have adopted distinctive ecological strategies throughout their period of coexistence. © 2017 The Author(s).

Sturgeon and paddlefish (Acipenseridae) saggital otoliths are composed of the calcium carbonate polymorphs vaterite and calcite: acipenseridae otoliths are vaterite and calcite

DOE PAGES

Pracheil, Brenda M.; Chakoumakos, Bryan C.; Feygenson, Mikhail; ...

2016-07-27

The otoliths of modern fishes are most commonly comprised of the metastable aragonite polymorph of calcium carbonate (CaCO3); however, sturgeons have otoliths reportedly comprised of the least stable of the three most-common polymorphs, vaterite. In this study, we used neutron diffraction to characterize CaCO3 polymorph composition of lake sturgeon and paddlefish otoliths. Based on previous summaries of CaCO3 composition over fish evolutionary history, we hypothesized that sturgeon and paddlefish otoliths would have similar polymorph composition. We found that despite previous reports of sturgeon otoliths being comprised entirely of vaterite, that all otoliths we examined in this study also had amore » calcite fraction that ranged from 17.9+ 6.0 wt. % to 35.9 + 2.9 wt. %. We also conducted a grinding experiment that demonstrated that calcite fractions were due to biological variation and not an artifact of polymorph transformation during preparation. Our study provides the initial characterization of the polymorph composition of the otoliths of lake sturgeon, and paddlefish and also provides the first-ever report of otoliths of Acipenserids as having a calcite fraction.« less

The effects of clothes on independent walking in toddlers.

PubMed

Théveniau, Nicolas; Boisgontier, Matthieu P; Varieras, Sabine; Olivier, Isabelle

2014-01-01

The spatiotemporal features of walking in toddlers are known to be related to the level of maturation of the central nervous system. However, previous studies did not assess whether there could be an effect of clothes on the acquisition of walking. In this study, it was hypothesized that clothes modify the toddlers' walking. To test this hypothesis, 22 healthy toddlers divided into 3 groups of walking experience were assessed in four clothing conditions (Diaper+Trousers; Diaper+Pants of tracksuit; Diaper; Underwear). Results revealed significant effects of clothing on velocity and step length of toddlers from 6 to 18 months of walking experience. These results suggested that biomechanical constraints induced by the textile features alter the walking of toddlers. Therefore, in studies of toddler's gait, the clothing worn should be carefully mentioned and controlled. Copyright © 2013 Elsevier B.V. All rights reserved.

Employee Trust in Supervisors and Affective Commitment: The Moderating Role of Authentic Leadership.

PubMed

Xiong, Kehan; Lin, Weipeng; Li, Jenny C; Wang, Lei

2016-06-01

Although previous research has examined the main/direct effects of subordinates' trust in their supervisors on the levels of subordinates' affective commitment towards the organizations, little attention has been paid to explore the boundary conditions of this relationship. Two studies were conducted to examine the moderating effect of authentic leadership on the relationship between subordinates' trust in supervisor and their levels of affective commitment towards the organization. In line with the hypothesized model, both Study 1 (cross-sectional design, n = 138) and Study 2 (lagged design, n = 154) demonstrated that authentic leadership moderated the relationship between employees' trust in supervisor and their levels of affective commitment towards their organizations. Specifically, the positive relationship was stronger for employees under higher levels of authentic leadership. The implications for theory and practice are discussed. © The Author(s) 2016.

A 3D QSAR CoMFA study of non-peptide angiotensin II receptor antagonists

NASA Astrophysics Data System (ADS)

Belvisi, Laura; Bravi, Gianpaolo; Catalano, Giovanna; Mabilia, Massimo; Salimbeni, Aldo; Scolastico, Carlo

1996-12-01

A series of non-peptide angiotensin II receptor antagonists was investigated with the aim of developing a 3D QSAR model using comparative molecular field analysis descriptors and approaches. The main goals of the study were dictated by an interest in methodologies and an understanding of the binding requirements to the AT1 receptor. Consistency with the previously derived activity models was always checked to contemporarily test the validity of the various hypotheses. The specific conformations chosen for the study, the procedures invoked to superimpose all structures, the conditions employed to generate steric and electrostatic field values and the various PCA/PLS runs are discussed in detail. The effect of experimental design techniques to select objects (molecules) and variables (descriptors) with respect to the predictive power of the QSAR models derived was especially analysed.

Role of U(VI) Reduction by Geobacter species

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

Lovely, Derrick

2008-12-23

Previous work had suggested that Acholeplasma palmae has a higher capacity for uranium sorption than other bacteria studied. Sorption studies were performed with cells in suspension in various solutions containing uranium, and results were used to generate uranium-biosorption isotherms. Results from this study showed that the U(VI) sorption capacity of G. uraniireducens was relatively similar in simple solutions, such as sodium chloride or bicarbonate. However, this ability to sorb uranium significantly decreased in groundwater. This suggested that certain chemicals present in the groundwater were inhibiting the ability of cell components of Geobacter to adsorb uranium. It was hypothesized that uraniummore » removal would also be diminished in the bicarbonate solution. However, this did not seem to be the case, as uranium was as easily removed in the bicarbonate solution as in the sodium chloride solution.« less

Comparative genomics in chicken and Pekin duck using FISH mapping and microarray analysis

PubMed Central

2009-01-01

Background The availability of the complete chicken (Gallus gallus) genome sequence as well as a large number of chicken probes for fluorescent in-situ hybridization (FISH) and microarray resources facilitate comparative genomic studies between chicken and other bird species. In a previous study, we provided a comprehensive cytogenetic map for the turkey (Meleagris gallopavo) and the first analysis of copy number variants (CNVs) in birds. Here, we extend this approach to the Pekin duck (Anas platyrhynchos), an obvious target for comparative genomic studies due to its agricultural importance and resistance to avian flu. Results We provide a detailed molecular cytogenetic map of the duck genome through FISH assignment of 155 chicken clones. We identified one inter- and six intrachromosomal rearrangements between chicken and duck macrochromosomes and demonstrated conserved synteny among all microchromosomes analysed. Array comparative genomic hybridisation revealed 32 CNVs, of which 5 overlap previously designated "hotspot" regions between chicken and turkey. Conclusion Our results suggest extensive conservation of avian genomes across 90 million years of evolution in both macro- and microchromosomes. The data on CNVs between chicken and duck extends previous analyses in chicken and turkey and supports the hypotheses that avian genomes contain fewer CNVs than mammalian genomes and that genomes of evolutionarily distant species share regions of copy number variation ("CNV hotspots"). Our results will expedite duck genomics, assist marker development and highlight areas of interest for future evolutionary and functional studies. PMID:19656363

Estimation of diastolic intraventricular pressure gradients by Doppler M-mode echocardiography

NASA Technical Reports Server (NTRS)

Greenberg, N. L.; Vandervoort, P. M.; Firstenberg, M. S.; Garcia, M. J.; Thomas, J. D.

2001-01-01

Previous studies have shown that small intraventricular pressure gradients (IVPG) are important for efficient filling of the left ventricle (LV) and as a sensitive marker for ischemia. Unfortunately, there has previously been no way of measuring these noninvasively, severely limiting their research and clinical utility. Color Doppler M-mode (CMM) echocardiography provides a spatiotemporal velocity distribution along the inflow tract throughout diastole, which we hypothesized would allow direct estimation of IVPG by using the Euler equation. Digital CMM images, obtained simultaneously with intracardiac pressure waveforms in six dogs, were processed by numerical differentiation for the Euler equation, then integrated to estimate IVPG and the total (left atrial to left ventricular apex) pressure drop. CMM-derived estimates agreed well with invasive measurements (IVPG: y = 0.87x + 0.22, r = 0.96, P < 0.001, standard error of the estimate = 0.35 mmHg). Quantitative processing of CMM data allows accurate estimation of IVPG and tracking of changes induced by beta-adrenergic stimulation. This novel approach provides unique information on LV filling dynamics in an entirely noninvasive way that has previously not been available for assessment of diastolic filling and function.

Daily spillover from family to work: A test of the work-home resources model.

PubMed

Du, Danyang; Derks, Daantje; Bakker, Arnold B

2018-04-01

The present study examines a mediated moderation model of the day-level effects of family hassles and family-work spillover (affect and cognition) on the relationship between job resources and employees' flourishing at work. Based on the work-home resources model, the authors hypothesized that demands from one domain (family) induce repetitive thoughts or negative feelings about those problems, so that individuals are not able to function optimally and to make full use of contextual resources in the other domain (work). Multilevel analyses of 108 Chinese working parents' 366 daily surveys revealed that the relationship between morning job resources and afternoon flourishing was significantly positive when previous day family hassles were low; the relationship became nonsignificant when previous day family hassles were high. In addition, as predicted, daily rumination also attenuated the relationship between morning job resources and afternoon flourishing, whereas daily affect did not. Finally, the moderating effect of previous day family hassles was mediated by daily rumination. The findings contribute to spillover theories by revealing the roles of affective and cognitive spillover from family to work. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

The Glass Is Half Full: Evidence for Efficacy of Alcohol-Wise at One University But Not the Other

PubMed Central

CROOM, KATHERINE; STAIANO-COICO, LISA; LESSER, MARTIN L.; LEWIS, DEBORAH K.; REYNA, VALERIE F.; MARCHELL, TIMOTHY C.; FRANK, JEREMY; IVES, STEPHANIE

2017-01-01

This research extends the growing literature about online alcohol prevention programs for first-year college students. Two independent randomized control studies, conducted at separate universities, evaluated the short-term effectiveness of Alcohol-Wise, an online alcohol prevention program not previously studied. It was hypothesized the prevention program would increase alcohol knowledge and reduce alcohol consumption, including high-risk alcohol-related behaviors, among first-year college students. At both universities, the intervention significantly increased alcohol-related knowledge. At one university, the prevention program also significantly reduced alcohol consumption and high-risk drinking behaviors, such as playing drinking games, heavy drinking, and extreme ritualistic alcohol consumption. Implications for the use of online alcohol prevention programs and student affairs are discussed. PMID:25909233

Neural Correlates of Reflection on Present and Past Selves in Autism Spectrum Disorder.

PubMed

Cygan, Hanna B; Marchewka, Artur; Kotlewska, Ilona; Nowicka, Anna

2018-06-05

Previous studies indicate that autobiographical memory is impaired in individuals with autism spectrum disorder (ASD). Successful recollection of information referring to one's own person requires the intact ability to re-activate representation of the past self. In the current fMRI study we investigated process of conscious reflection on the present self, the past self, and a close-other in the ASD and typically developing groups. Significant inter-group differences were found in the Past-Self condition. In individuals with ASD, reflection on the past self was associated with additional engagement of the posterior cingulate and posterior temporal structures. We hypothesize that this enhanced activation of widely distributed neural network reflects substantial difficulties in processes of reflection on one's own person in the past.

Parametric and non-parametric modeling of short-term synaptic plasticity. Part I: computational study

PubMed Central

Marmarelis, Vasilis Z.; Berger, Theodore W.

2009-01-01

Parametric and non-parametric modeling methods are combined to study the short-term plasticity (STP) of synapses in the central nervous system (CNS). The nonlinear dynamics of STP are modeled by means: (1) previously proposed parametric models based on mechanistic hypotheses and/or specific dynamical processes, and (2) non-parametric models (in the form of Volterra kernels) that transforms the presynaptic signals into postsynaptic signals. In order to synergistically use the two approaches, we estimate the Volterra kernels of the parametric models of STP for four types of synapses using synthetic broadband input–output data. Results show that the non-parametric models accurately and efficiently replicate the input–output transformations of the parametric models. Volterra kernels provide a general and quantitative representation of the STP. PMID:18506609

Temporal Dynamics of Hypothesis Generation: The Influences of Data Serial Order, Data Consistency, and Elicitation Timing

PubMed Central

Lange, Nicholas D.; Thomas, Rick P.; Davelaar, Eddy J.

2012-01-01

The pre-decisional process of hypothesis generation is a ubiquitous cognitive faculty that we continually employ in an effort to understand our environment and thereby support appropriate judgments and decisions. Although we are beginning to understand the fundamental processes underlying hypothesis generation, little is known about how various temporal dynamics, inherent in real world generation tasks, influence the retrieval of hypotheses from long-term memory. This paper presents two experiments investigating three data acquisition dynamics in a simulated medical diagnosis task. The results indicate that the mere serial order of data, data consistency (with previously generated hypotheses), and mode of responding influence the hypothesis generation process. An extension of the HyGene computational model endowed with dynamic data acquisition processes is forwarded and explored to provide an account of the present data. PMID:22754547

Temperature, routine activities, and domestic violence: a reanalysis.

PubMed

Rotton, J; Cohn, E G

2001-04-01

It was hypothesized that base rate differences in the number of complaints made during daylight and nighttime hours were responsible for a previously reported, nonlinear relationship between temperature and domestic violence. This hypothesis was tested by subjecting calls for service in 1987 and 1988 in Minneapolis, to moderator-variable regression analyses with controls for time of day, day of the week, season, and their interactions as well as linear trend, major holidays, public school closings, the first day of the month, and other weather variables. Temporal variables explained 75% of the variance in calls for service. As hypothesized, the base rate artifact was responsible for an apparent downturn in violence at high temperatures: Fewer complaints were received during afternoon hours, because they happen to be the warmest time of the day. The results were interpreted in terms of routine activity theory.

Evolution of the premaxillary fraenum and substratum in snubnose darters and allies (Percidae: Etheostoma).

PubMed

Ciccotto, P J; Mendelson, T C

2015-10-01

Darters (Percidae: Etheostomatinae), a species-rich group of North American freshwater fishes, vary in the presence of a premaxillary fraenum, a strip of skin that connects the premaxillary bones to the snout, and it is hypothesized that this trait is a trophic adaptation to particular substrata. Ancestral state reconstructions and analyses of phylogenetic associations between presence of the premaxillary fraenum and preferred stream substratum were conducted in a clade of closely related darters (snubnose darters and allies) that vary in morphology and habitat preferences. The most recent common ancestor of this clade was inferred to possess a fraenum and to inhabit rocky substrata, consistent with previous hypotheses, but a significant correlation between fraenum presence and substratum type across the phylogeny was not found. © 2015 The Fisheries Society of the British Isles.

Transcranial Direct Current Stimulation of the Temporoparietal Junction and Inferior Frontal Cortex Improves Imitation-Inhibition and Perspective-Taking with no Effect on the Autism-Spectrum Quotient Score.

PubMed

Nobusako, Satoshi; Nishi, Yuki; Nishi, Yuki; Shuto, Takashi; Asano, Daiki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Lesions to brain regions such as the temporoparietal junction (TPJ) and inferior frontal cortex (IFC) are thought to cause autism-spectrum disorder (ASD). Previous studies indicated that transcranial direct current stimulation (tDCS) of the right TPJ improves social cognitive functions such as imitation-inhibition and perspective-taking. Although previous work shows that tDCS of the right IFC improves imitation-inhibition, its effects on perspective-taking have yet to be determined. In addition, the role of the TPJ and IFC in determining the Autism-Spectrum Quotient (AQ), which is a measure of autism spectrum traits, is still unclear. Thus, the current study performed tDCS on the right TPJ and the right IFC of healthy adults, and examined its effects on imitation-inhibition, perspective-taking and AQ scores. Based on previous studies, we hypothesized that anodal tDCS of the right IFC and right TPJ would improve imitation-inhibition, perspective-taking and the AQ score. Anodal tDCS of the right TPJ or IFC significantly decreased the interference effect in an imitation-inhibition task and the cost of perspective-taking in a perspective-taking task, in comparison to the sham stimulation control. These findings indicated that both the TPJ and the IFC play a role in imitation-inhibition and perspective-taking, i.e., control of self and other representations. However, anodal stimulation of the right TPJ and the right IFC did not alter participants' AQ. This finding conflicts with results from previous brain imaging studies, which could be attributed to methodological differences such as variation in sex, age and ASD. Therefore, further research is necessary to determine the relationship between the TPJ and IFC, and the AQ.

Transcranial Direct Current Stimulation of the Temporoparietal Junction and Inferior Frontal Cortex Improves Imitation-Inhibition and Perspective-Taking with no Effect on the Autism-Spectrum Quotient Score

PubMed Central

Nobusako, Satoshi; Nishi, Yuki; Nishi, Yuki; Shuto, Takashi; Asano, Daiki; Osumi, Michihiro; Morioka, Shu

2017-01-01

Lesions to brain regions such as the temporoparietal junction (TPJ) and inferior frontal cortex (IFC) are thought to cause autism-spectrum disorder (ASD). Previous studies indicated that transcranial direct current stimulation (tDCS) of the right TPJ improves social cognitive functions such as imitation-inhibition and perspective-taking. Although previous work shows that tDCS of the right IFC improves imitation-inhibition, its effects on perspective-taking have yet to be determined. In addition, the role of the TPJ and IFC in determining the Autism-Spectrum Quotient (AQ), which is a measure of autism spectrum traits, is still unclear. Thus, the current study performed tDCS on the right TPJ and the right IFC of healthy adults, and examined its effects on imitation-inhibition, perspective-taking and AQ scores. Based on previous studies, we hypothesized that anodal tDCS of the right IFC and right TPJ would improve imitation-inhibition, perspective-taking and the AQ score. Anodal tDCS of the right TPJ or IFC significantly decreased the interference effect in an imitation-inhibition task and the cost of perspective-taking in a perspective-taking task, in comparison to the sham stimulation control. These findings indicated that both the TPJ and the IFC play a role in imitation-inhibition and perspective-taking, i.e., control of self and other representations. However, anodal stimulation of the right TPJ and the right IFC did not alter participants’ AQ. This finding conflicts with results from previous brain imaging studies, which could be attributed to methodological differences such as variation in sex, age and ASD. Therefore, further research is necessary to determine the relationship between the TPJ and IFC, and the AQ. PMID:28536512

Endocrine and metabolic effects of consuming beverages sweetened with fructose, glucose, sucrose, or high-fructose corn syrup.

PubMed

Stanhope, Kimber L; Havel, Peter J

2008-12-01

Our laboratory has investigated 2 hypotheses regarding the effects of fructose consumption: 1) the endocrine effects of fructose consumption favor a positive energy balance, and 2) fructose consumption promotes the development of an atherogenic lipid profile. In previous short- and long-term studies, we showed that consumption of fructose-sweetened beverages with 3 meals results in lower 24-h plasma concentrations of glucose, insulin, and leptin in humans than does consumption of glucose-sweetened beverages. We have also tested whether prolonged consumption of high-fructose diets leads to increased caloric intake or decreased energy expenditure, thereby contributing to weight gain and obesity. Results from a study conducted in rhesus monkeys produced equivocal results. Carefully controlled and adequately powered long-term studies are needed to address these hypotheses. In both short- and long-term studies, we showed that consumption of fructose-sweetened beverages substantially increases postprandial triacylglycerol concentrations compared with glucose-sweetened beverages. In the long-term studies, apolipoprotein B concentrations were also increased in subjects consuming fructose, but not in those consuming glucose. Data from a short-term study comparing consumption of beverages sweetened with fructose, glucose, high-fructose corn syrup, and sucrose suggest that high-fructose corn syrup and sucrose increase postprandial triacylglycerol to an extent comparable with that induced by 100% fructose alone. Increased consumption of fructose-sweetened beverages along with increased prevalence of obesity, metabolic syndrome, and type 2 diabetes underscore the importance of investigating the metabolic consequences of fructose consumption in carefully controlled experiments.

Overt versus covert conduct disorder symptoms and the prospective prediction of antisocial personality disorder.

PubMed

Le Corff, Yann; Toupin, Jean

2014-12-01

Studies have shown strong continuity between conduct disorder (CD) in adolescence and antisocial personality disorder (APD) in adulthood. Researchers have been trying to explain why some adolescents with CD persist into adult APD and others do not. A few studies reported that overt and covert CD symptoms have a differential predictive power for APD, with mixed results. The present study aimed to evaluate the prospective association of overt and covert CD symptoms with APD in a sample of male adolescents with CD (N = 128, mean age = 15.6, SD = 1.6). Participants were recruited at intake in Quebec Youth Centers and reassessed 3 years later (n = 73). CD and ADHD symptoms were assessed at intake with the DISC-R while APD was assessed 3 years later with the SCID-II. Logistic regression results showed that, contrary to previous prospective studies (Lahey, Loeber, Burke, & Applegate, 2005; Washburn et al., 2007), overt (OR = 2.12, 95% CI [1.29, 3.50]) but not covert (OR = 1.04, 95% CI [0.69, 1.56]) symptoms predicted later APD, controlling for ADHD symptoms and socioeconomic status. It is hypothesized that the divergence with previous studies may be explained by the higher mean number and wider range of overt CD symptoms in our sample.

Constraint, natural selection, and the evolution of human body form

PubMed Central

Savell, Kristen R. R.; Auerbach, Benjamin M.; Roseman, Charles C.

2016-01-01

Variation in body form among human groups is structured by a blend of natural selection driven by local climatic conditions and random genetic drift. However, attempts to test ecogeographic hypotheses have not distinguished between adaptive traits (i.e., those that evolved as a result of selection) and those that evolved as a correlated response to selection on other traits (i.e., nonadaptive traits), complicating our understanding of the relationship between climate and morphological distinctions among populations. Here, we use evolutionary quantitative methods to test if traits previously identified as supporting ecogeographic hypotheses were actually adaptive by estimating the force of selection on individual traits needed to drive among-group differentiation. Our results show that not all associations between trait means and latitude were caused by selection acting directly on each individual trait. Although radial and tibial length and biiliac and femoral head breadth show signs of responses to directional selection matching ecogeographic hypotheses, the femur was subject to little or no directional selection despite having shorter values by latitude. Additionally, in contradiction to ecogeographic hypotheses, the humerus was under directional selection for longer values by latitude. Responses to directional selection in the tibia and radius induced a nonadaptive correlated response in the humerus that overwhelmed its own trait-specific response to selection. This result emphasizes that mean differences between groups are not good indicators of which traits are adaptations in the absence of information about covariation among characteristics. PMID:27482101

Constraint, natural selection, and the evolution of human body form.

PubMed

Savell, Kristen R R; Auerbach, Benjamin M; Roseman, Charles C

2016-08-23

Variation in body form among human groups is structured by a blend of natural selection driven by local climatic conditions and random genetic drift. However, attempts to test ecogeographic hypotheses have not distinguished between adaptive traits (i.e., those that evolved as a result of selection) and those that evolved as a correlated response to selection on other traits (i.e., nonadaptive traits), complicating our understanding of the relationship between climate and morphological distinctions among populations. Here, we use evolutionary quantitative methods to test if traits previously identified as supporting ecogeographic hypotheses were actually adaptive by estimating the force of selection on individual traits needed to drive among-group differentiation. Our results show that not all associations between trait means and latitude were caused by selection acting directly on each individual trait. Although radial and tibial length and biiliac and femoral head breadth show signs of responses to directional selection matching ecogeographic hypotheses, the femur was subject to little or no directional selection despite having shorter values by latitude. Additionally, in contradiction to ecogeographic hypotheses, the humerus was under directional selection for longer values by latitude. Responses to directional selection in the tibia and radius induced a nonadaptive correlated response in the humerus that overwhelmed its own trait-specific response to selection. This result emphasizes that mean differences between groups are not good indicators of which traits are adaptations in the absence of information about covariation among characteristics.

Lumbar muscle dysfunction during remission of unilateral recurrent nonspecific low-back pain: evaluation with muscle functional MRI.

PubMed

D'hooge, Roseline; Cagnie, Barbara; Crombez, Geert; Vanderstraeten, Guy; Achten, Eric; Danneels, Lieven

2013-03-01

After cessation of a low-back pain (LBP) episode, alterations in trunk muscle behavior, despite recovery from pain, have been hypothesized to play a pathogenic role in the recurrence of LBP. This study aimed to identify the presence of lumbar muscle dysfunction during the remission of recurrent LBP, while performing a low-load trunk-extension movement. Thirteen participants with unilateral recurrent LBP were tested at least 1 month after cessation of the previous LBP episode and were compared with a healthy control group without any history of LBP (n=13). Also, differences between previously painful and nonpainful sides were examined. Muscle functional magnetic resonance imaging, based on quantitative T2-imaging, was used to examine muscle tissue characteristics (T2 rest) and muscle recruitment (T2 shift) during prone trunk extension. The lumbar multifidus, erector spinae, quadratus lumborum, and psoas were bilaterally visualized on 2 lumbar levels using a T2-weighted (spin-echo multicontrast) magnetic resonance imaging sequence. Linear mixed model analysis revealed a significantly lower T2 rest (P=0.044) and a significantly higher T2 shift (P=0.034) solely for the multifidus in the LBP group compared with the control group. No significant differences between pain sides were found. Lower T2-rest values have been suggested to correlate with a conversion of the multifidus' fiber typing toward the glycolytic muscle spectrum. Elevated T2 shifts correspond with increased levels of metabolic activity in the multifidus in the LBP group, for which several hypotheses can be put forward. Taken together, these findings provide evidence of concurrent alterations in the multifidus structure and activity in individuals with unilateral recurrent LBP, despite being pain free and functionally recovered.

Littorally adaptive? Testing the link between habitat, morphology, and reproduction in the intertidal sculpin subfamily Oligocottinae (Pisces: Cottoidea).

PubMed

Buser, Thaddaeus J; Burns, Michael D; López, J Andrés

2017-01-01

While intertidal habitats are often productive, species-rich environments, they are also harsh and highly dynamic. Organisms that live in these habitats must possess morphological and physiological adaptations that enable them to do so. Intertidal fishes are generally small, often lack scales, and the diverse families represented in intertidal habitats often show convergence into a few general body shapes. However, few studies have quantified the relationship between phenotypes and intertidal living. Likewise, the diversity of reproductive traits and parental care in intertidal fishes has yet to be compared quantitatively with habitat. We examine the relationship of these characters in the sculpin subfamily Oligocottinae using a phylogenetic hypothesis, geometric morphometrics, and phylogenetic comparative methods to provide the first formal test of associations between fish phenotypes and reproductive characters with intertidal habitats. We show that the ability to live in intertidal habitats, particularly in tide pools, is likely a primitive state for Oligocottinae, with a single species that has secondarily come to occupy only subtidal habitats. Contrary to previous hypotheses, maximum size and presence of scales do not show a statistically significant correlation with depth. However, the maximum size for all species is generally small (250 mm or less) and all show a reduction in scales, as would be expected for an intertidal group. Also contrary to previous hypotheses, we show that copulation and associated characters are the ancestral condition in Oligocottinae, with copulation most likely being lost in a single lineage within the genus Artedius . Lastly, we show that body shape appears to be constrained among species with broader depth ranges, but lineages that occupy only a narrow range of intertidal habitats display novel body shapes, and this may be associated with habitat partitioning, particularly as it relates to the degree of wave exposure.

The effect of a concurrent cognitive task on cortical potentials evoked by unpredictable balance perturbations

PubMed Central

Quant, Sylvia; Adkin, Allan L; Staines, W Richard; Maki, Brian E; McIlroy, William E

2004-01-01

Background Although previous studies suggest that postural control requires attention and other cognitive resources, the central mechanisms responsible for this relationship remain unclear. To address this issue, we examined the effects of altered attention on cortical activity and postural responses following mechanical perturbations to upright stance. We hypothesized that cortical activity would be attenuated but not delayed when mechanical perturbations were applied during a concurrent performance of a cognitive task (i.e. when attention was directed away from the perturbation). We also hypothesized that these cortical changes would be accompanied by alterations in the postural response, as evidenced by increases in the magnitude of anteroposterior (AP) centre of pressure (COP) peak displacements and tibialis anterior (TA) muscle activity. Healthy young adults (n = 7) were instructed to continuously track (cognitive task) or not track (control task) a randomly moving visual target using a hand-held joystick. During each of these conditions, unpredictable translations of a moving floor evoked cortical and postural responses. Scalp-recorded cortical activity, COP, and TA electromyographic (EMG) measures were collected. Results Results revealed a significant decrease in the magnitude of early cortical activity (the N1 response, the first negative peak after perturbation onset) during the tracking task compared to the control condition. More pronounced AP COP peak displacements and EMG magnitudes were also observed for the tracking task and were possibly related to changes in the N1 response. Conclusion Based on previous notions that the N1 response represents sensory processing of the balance disturbance, we suggest that the attenuation of the N1 response is an important central mechanism that may provide insight into the relationship between attention and postural control. PMID:15147586

The effect of a concurrent cognitive task on cortical potentials evoked by unpredictable balance perturbations.

PubMed

Quant, Sylvia; Adkin, Allan L; Staines, W Richard; Maki, Brian E; McIlroy, William E

2004-05-17

Although previous studies suggest that postural control requires attention and other cognitive resources, the central mechanisms responsible for this relationship remain unclear. To address this issue, we examined the effects of altered attention on cortical activity and postural responses following mechanical perturbations to upright stance. We hypothesized that cortical activity would be attenuated but not delayed when mechanical perturbations were applied during a concurrent performance of a cognitive task (i.e. when attention was directed away from the perturbation). We also hypothesized that these cortical changes would be accompanied by alterations in the postural response, as evidenced by increases in the magnitude of anteroposterior (AP) centre of pressure (COP) peak displacements and tibialis anterior (TA) muscle activity. Healthy young adults (n = 7) were instructed to continuously track (cognitive task) or not track (control task) a randomly moving visual target using a hand-held joystick. During each of these conditions, unpredictable translations of a moving floor evoked cortical and postural responses. Scalp-recorded cortical activity, COP, and TA electromyographic (EMG) measures were collected. Results revealed a significant decrease in the magnitude of early cortical activity (the N1 response, the first negative peak after perturbation onset) during the tracking task compared to the control condition. More pronounced AP COP peak displacements and EMG magnitudes were also observed for the tracking task and were possibly related to changes in the N1 response. Based on previous notions that the N1 response represents sensory processing of the balance disturbance, we suggest that the attenuation of the N1 response is an important central mechanism that may provide insight into the relationship between attention and postural control.

Grey matter volume patterns in thalamic nuclei are associated with familial risk for schizophrenia.

PubMed

Pergola, Giulio; Trizio, Silvestro; Di Carlo, Pasquale; Taurisano, Paolo; Mancini, Marina; Amoroso, Nicola; Nettis, Maria Antonietta; Andriola, Ileana; Caforio, Grazia; Popolizio, Teresa; Rampino, Antonio; Di Giorgio, Annabella; Bertolino, Alessandro; Blasi, Giuseppe

2017-02-01

Previous evidence suggests reduced thalamic grey matter volume (GMV) in patients with schizophrenia (SCZ). However, it is not considered an intermediate phenotype for schizophrenia, possibly because previous studies did not assess the contribution of individual thalamic nuclei and employed univariate statistics. Here, we hypothesized that multivariate statistics would reveal an association of GMV in different thalamic nuclei with familial risk for schizophrenia. We also hypothesized that accounting for the heterogeneity of thalamic GMV in healthy controls would improve the detection of subjects at familial risk for the disorder. We acquired MRI scans for 96 clinically stable SCZ, 55 non-affected siblings of patients with schizophrenia (SIB), and 249 HC. The thalamus was parceled into seven regions of interest (ROIs). After a canonical univariate analysis, we used GMV estimates of thalamic ROIs, together with total thalamic GMV and premorbid intelligence, as features in Random Forests to classify HC, SIB, and SCZ. Then, we computed a Misclassification Index for each individual and tested the improvement in SIB detection after excluding a subsample of HC misclassified as patients. Random Forests discriminated SCZ from HC (accuracy=81%) and SIB from HC (accuracy=75%). Left anteromedial thalamic volumes were significantly associated with both multivariate classifications (p<0.05). Excluding HC misclassified as SCZ improved greatly HC vs. SIB classification (Cohen's d=1.39). These findings suggest that multivariate statistics identify a familial background associated with thalamic GMV reduction in SCZ. They also suggest the relevance of inter-individual variability of GMV patterns for the discrimination of individuals at familial risk for the disorder. Copyright © 2016 Elsevier B.V. All rights reserved.

Digital micromirror device (DMD)-based 3D printing of poly(propylene fumarate) scaffolds.

PubMed

Mott, Eric J; Busso, Mallory; Luo, Xinyi; Dolder, Courtney; Wang, Martha O; Fisher, John P; Dean, David

2016-04-01

Our recent investigations into the 3D printing of poly(propylene fumarate) (PPF), a linear polyester, using a DMD-based system brought us to a resin that used titanium dioxide (TiO2) as an ultraviolet (UV) filter for controlling cure depth. However, this material hindered the 3D printing process due to undesirable lateral or "dark" curing (i.e., in areas not exposed to light from the DMD chip). Well known from its use in sunscreen, another UV filter, oxybenzone, has previously been used in conjunction with TiO2. In this study we hypothesize that combining these two UV filters will result in a synergistic effect that controls cure depth and avoids dark cure. A resin mixture (i.e., polymer, initiator, UV filters) was identified that worked well. The resin was then further characterized through mechanical testing, cure testing, and cytotoxicity testing to investigate its use as a material for bone tissue engineering scaffolds. Results show that the final resin eliminated dark cure as shown through image analysis. Mechanically the new scaffolds proved to be far weaker than those printed from previous resins, with compressive strengths of 7.8 ± 0.5 MPa vs. 36.5 ± 1.6 MPa, respectively. The new scaffolds showed a 90% reduction in elastic modulus and a 74% increase in max strain. These properties may be useful in tissue engineering applications where resorption is required. Initial cytotoxicity evaluation was negative. As hypothesized, the use of TiO2 and oxybenzone showed synergistic effects in the 3D printing of PPF tissue engineering scaffolds. Copyright © 2015 Elsevier B.V. All rights reserved.

The developmental basis of an evolutionary diversification of female gametophyte structure in Piper and Piperaceae

PubMed Central

Madrid, Eric N.; Friedman, William E.

2009-01-01

Background and Aims Fritillaria-type female gametophyte development is a complex, yet homoplasious developmental pattern that is interesting from both evolutionary and developmental perspectives. Piper (Piperaceae) was chosen for this study of Fritillaria-type female gametophyte development because Piperales represent a ‘hotspot’ of female gametophyte developmental evolution and have been the subject of several recent molecular phylogenetic analyses. This wealth of phylogenetic and descriptive data make Piper an excellent candidate for inferring the evolutionary developmental basis for the origin of Fritillaria-type female gametophytes. Methods Developing ovules of Piper peltatum were taken from greenhouse collections, embedded in glycol methacrylate, and serially sectioned. Light microscopy and laser scanning confocal microscopy were combined to produce three-dimensional computer reconstructions of developing female gametophytes. The ploidies of the developing embryos and endosperms were calculated using microspectrofluorometry. Key Results The data describe female gametophyte development in Piper with highly detailed three-dimensional models, and document two previously unknown arrangements of megaspore nuclei during early development. Also collected were microspectrofluorometric data that indicate that Fritillaria-type female gametophyte development in Piper results in pentaploid endosperm. Conclusions The three-dimensional models resolve previous ambiguities in developmental interpretations of Fritillaria-type female gametophytes in Piper. The newly discovered arrangements of megaspore nuclei that are described allow for the construction of explicit hypotheses of female gametophyte developmental evolution within Piperaceae, and more broadly throughout Piperales. These detailed hypotheses indicate that the common ancestor of Piperaceae minus Verhuellia had a Drusa-type female gametophyte, and that evolutionary transitions to derived tetrasporic female gametophyte ontogenies in Piperaceae, including Fritillaria-type female gametophyte development, are the consequence of key nuclear migration and patterning events at the end of megasporogenesis. PMID:19202137

Evidence suggesting digenic inheritance of Waardenburg syndrome type II with ocular albinism.

PubMed

Chiang, Pei-Wen; Spector, Elaine; McGregor, Tracy L

2009-12-01

Waardenburg syndrome (WS) is a series of auditory-pigmentary disorders inherited in an autosomal dominant manner. In most patients, WS2 results from mutations in the MITF gene. MITF encodes a basic helix-loop-helix transcription factor that activates transcription of tyrosinase and other melanocyte proteins. The clinical presentation of WS is highly variable, and we believe that Tietz syndrome and WS2 with ocular albinism (OA) are likely two variations of WS2 due to the presence of modifiers. One family with a molecular diagnosis of WS2 co-segregating with OA has previously been reported. A digenic mutation mechanism including both a MITF mutation and the TYR(R402Q) hypomorphic allele was proposed to be the cause of OA in this family. Here, we present a second WS2 family with OA and provide evidence suggesting the TYR(R402Q) allele does not cause OA in this family. We hypothesize the presence of a novel OCA3 mutation together with the MITF del p.R217 mutation account for the OA phenotype in this family. Since MITF is a transcription factor for pigmentation genes, a mutation in MITF plus a heterozygous mutation in OCA3 together provide an adverse effect crossing a quantitative threshold; therefore, WS2 with OA occurs. We have hypothesized previously that the clinical spectrum and mutation mechanism of OCA depend on the pigmentation threshold of an affected individual. This unique family has provided further evidence supporting this hypothesis. We suggest that by studying OCA patients alongside WS patients with various pigmentation profiles we can facilitate further understanding of the pigmentation pathway.

Discovery of piragliatin--first glucokinase activator studied in type 2 diabetic patients.

PubMed

Sarabu, Ramakanth; Bizzarro, Fred T; Corbett, Wendy L; Dvorozniak, Mark T; Geng, Wanping; Grippo, Joseph F; Haynes, Nancy-Ellen; Hutchings, Stanley; Garofalo, Lisa; Guertin, Kevin R; Hilliard, Darryl W; Kabat, Marek; Kester, Robert F; Ka, Wang; Liang, Zhenmin; Mahaney, Paige E; Marcus, Linda; Matschinsky, Franz M; Moore, David; Racha, Jagdish; Radinov, Roumen; Ren, Yi; Qi, Lida; Pignatello, Michael; Spence, Cheryl L; Steele, Thomas; Tengi, John; Grimsby, Joseph

2012-08-23

Glucokinase (GK) activation as a potential strategy to treat type 2 diabetes (T2D) is well recognized. Compound 1, a glucokinase activator (GKA) lead that we have previously disclosed, caused reversible hepatic lipidosis in repeat-dose toxicology studies. We hypothesized that the hepatic lipidosis was due to the structure-based toxicity and later established that it was due to the formation of a thiourea metabolite, 2. Subsequent SAR studies of 1 led to the identification of a pyrazine-based lead analogue 3, lacking the thiazole moiety. In vivo metabolite identification studies, followed by the independent synthesis and profiling of the cyclopentyl keto- and hydroxyl- metabolites of 3, led to the selection of piragliatin, 4, as the clinical lead. Piragliatin was found to lower pre- and postprandial glucose levels, improve the insulin secretory profile, increase β-cell sensitivity to glucose, and decrease hepatic glucose output in patients with T2D.

Is perceived emotional support beneficial? Well-being and health in independent and interdependent cultures.

PubMed

Uchida, Yukiko; Kitayama, Shinobu; Mesquita, Batja; Reyes, Jose Alberto S; Morling, Beth

2008-06-01

Previous studies show there is little or no association between perceived emotional support and well-being in European American culture. The authors hypothesized that this paradoxical absence of any benefit of perceived support is unique to cultural contexts that privilege independence rather than interdependence of the self. Study 1 tested college students and found, as predicted, that among Euro-Americans a positive effect of perceived emotional support on subjective well-being (positive affect) was weak and, moreover, it disappeared entirely once self-esteem was statistically controlled. In contrast, among Asians in Asia (Japanese and Filipinos) perceived emotional support positively predicted subjective well-being even after self-esteem was controlled. Study 2 extended Study 1 by testing both Japanese and American adults in midlife with respect to multiple indicators of well-being and physical health. Overall, the evidence underscores the central significance of culture as a moderator of the effectiveness of perceived emotional support.

Multimodal Emotion Recognition Is Resilient to Insufficient Sleep: Results From Cross-Sectional and Experimental Studies.

PubMed

Holding, Benjamin C; Laukka, Petri; Fischer, Håkan; Bänziger, Tanja; Axelsson, John; Sundelin, Tina

2017-11-01

Insufficient sleep has been associated with impaired recognition of facial emotions. However, previous studies have found inconsistent results, potentially stemming from the type of static picture task used. We therefore examined whether insufficient sleep was associated with decreased emotion recognition ability in two separate studies using a dynamic multimodal task. Study 1 used a cross-sectional design consisting of 291 participants with questionnaire measures assessing sleep duration and self-reported sleep quality for the previous night. Study 2 used an experimental design involving 181 participants where individuals were quasi-randomized into either a sleep-deprivation (N = 90) or a sleep-control (N = 91) condition. All participants from both studies were tested on the same forced-choice multimodal test of emotion recognition to assess the accuracy of emotion categorization. Sleep duration, self-reported sleep quality (study 1), and sleep deprivation (study 2) did not predict overall emotion recognition accuracy or speed. Similarly, the responses to each of the twelve emotions tested showed no evidence of impaired recognition ability, apart from one positive association suggesting that greater self-reported sleep quality could predict more accurate recognition of disgust (study 1). The studies presented here involve considerably larger samples than previous studies and the results support the null hypotheses. Therefore, we suggest that the ability to accurately categorize the emotions of others is not associated with short-term sleep duration or sleep quality and is resilient to acute periods of insufficient sleep. © Sleep Research Society 2017. Published by Oxford University Press on behalf of the Sleep Research Society. All rights reserved. For permissions, please e-mail journals.permissions@oup.com.

Yoga, Meditation and Mind-Body Health: Increased BDNF, Cortisol Awakening Response, and Altered Inflammatory Marker Expression after a 3-Month Yoga and Meditation Retreat.

PubMed

Cahn, B Rael; Goodman, Matthew S; Peterson, Christine T; Maturi, Raj; Mills, Paul J

2017-01-01

Thirty-eight individuals (mean age: 34.8 years old) participating in a 3-month yoga and meditation retreat were assessed before and after the intervention for psychometric measures, brain derived neurotrophic factor (BDNF), circadian salivary cortisol levels, and pro- and anti-inflammatory cytokines. Participation in the retreat was found to be associated with decreases in self-reported anxiety and depression as well as increases in mindfulness. As hypothesized, increases in the plasma levels of BDNF and increases in the magnitude of the cortisol awakening response (CAR) were also observed. The normalized change in BDNF levels was inversely correlated with BSI-18 anxiety scores at both the pre-retreat ( r = 0.40, p < 0.05) and post-retreat ( r = 0.52, p < 0.005) such that those with greater anxiety scores tended to exhibit smaller pre- to post-retreat increases in plasma BDNF levels. In line with a hypothesized decrease in inflammatory processes resulting from the yoga and meditation practices, we found that the plasma level of the anti-inflammatory cytokine Interleukin-10 was increased and the pro-inflammatory cytokine Interleukin-12 was reduced after the retreat. Contrary to our initial hypotheses, plasma levels of other pro-inflammatory cytokines, including Interferon Gamma (IFN-γ), Tumor Necrosis Factor (TNF-α), Interleukin-1β (IL-1β), Interleukin-6 (IL-6), and Interleukin-8 (IL-8) were increased after the retreat. Given evidence from previous studies of the positive effects of meditative practices on mental fitness, autonomic homeostasis and inflammatory status, we hypothesize that these findings are related to the meditative practices throughout the retreat; however, some of the observed changes may also be related to other aspects of the retreat such as physical exercise-related components of the yoga practice and diet. We hypothesize that the patterns of change observed here reflect mind-body integration and well-being. The increased BDNF levels observed is a potential mediator between meditative practices and brain health, the increased CAR is likely a reflection of increased dynamic physiological arousal, and the relationship of the dual enhancement of pro- and anti-inflammatory cytokine changes to healthy immunologic functioning is discussed.

Autobiographical memory specificity in dissociative identity disorder.

PubMed

Huntjens, Rafaële J C; Wessel, Ineke; Hermans, Dirk; van Minnen, Agnes

2014-05-01

A lack of adequate access to autobiographical knowledge has been related to psychopathology. More specifically, patients suffering from depression or a history of trauma have been found to be characterized by overgeneral memory, in other words, they show a relative difficulty in retrieving a specific event from memory located in time and place. Previous studies of overgeneral memory have not included patients with dissociative disorders. These patients are interesting to consider, as they are hypothesized to have the ability to selectively compartmentalize information linked to negative emotions. This study examined avoidance and overgeneral memory in patients with dissociative identity disorder (DID; n = 12). The patients completed the autobiographical memory test (AMT). Their performance was compared with control groups of posttraumatic stress disorder (PTSD) patients (n = 26), healthy controls (n = 29), and DID simulators (n = 26). Specifically, we compared the performance of separate identity states in DID hypothesized to diverge in the use of avoidance as a coping strategy to deal with negative affect. No significant differences in memory specificity were found between the separate identities in DID. Irrespective of identity state, DID patients were characterized by a lack of memory specificity, which was similar to the lack of memory specificity found in PTSD patients. The converging results for DID and PTSD patients add empirical evidence for the role of overgeneral memory involved in the maintenance of posttraumatic psychopathology.

Large variation in mitochondrial DNA of sexual and parthenogenetic Dahlica triquetrella (Lepidoptera: Psychidae) shows multiple origins of parthenogenesis

PubMed Central

2013-01-01

Background Obligate parthenogenesis is relatively rare in animals. Still, in some groups it is quite common and has evolved and persisted multiple times. These groups may provide important clues to help solve the ‘paradox of sex’. Several species in the Psychidae (Lepidoptera) have obligate parthenogenesis. Dahlica triquetrella is one of those species where multiple transitions to parthenogenesis are postulated based on intensive cytological and behavioural studies. This has led to the hypothesis that multiple transitions from sexuals to diploid parthenogens occurred during and after the last glacial period, followed by transitions from parthenogenetic diploids to parthenogenetic tetraploids. Our study is the first to test these hypotheses using a molecular phylogeny based on mtDNA from multiple sexual and parthenogenetic populations from a wide geographic range. Results Parthenogenetic (and sexual) D. triquetrella are not monophyletic, and considerable sequence variation is present suggesting multiple transitions to parthenogenesis. However, we could not establish ancestral sexual haplotypes from our dataset. Our data suggest that some parthenogenetic clades have evolved, indicating origins of parthenogenesis before the last glacial period. Conclusions Multiple transitions to parthenogenesis have taken place in Dahlica triquetrella, confirming previous hypotheses. The number of different parthenogenetic clades, haplotypes and their apparent evolutionary age, clearly show that parthenogenesis has been a very successful reproductive strategy in this species over a long period. PMID:23622052

Large variation in mitochondrial DNA of sexual and parthenogenetic Dahlica triquetrella (Lepidoptera: Psychidae) shows multiple origins of parthenogenesis.

PubMed

Elzinga, Jelmer A; Jokela, Jukka; Shama, Lisa N S

2013-04-26

Obligate parthenogenesis is relatively rare in animals. Still, in some groups it is quite common and has evolved and persisted multiple times. These groups may provide important clues to help solve the 'paradox of sex'. Several species in the Psychidae (Lepidoptera) have obligate parthenogenesis. Dahlica triquetrella is one of those species where multiple transitions to parthenogenesis are postulated based on intensive cytological and behavioural studies. This has led to the hypothesis that multiple transitions from sexuals to diploid parthenogens occurred during and after the last glacial period, followed by transitions from parthenogenetic diploids to parthenogenetic tetraploids. Our study is the first to test these hypotheses using a molecular phylogeny based on mtDNA from multiple sexual and parthenogenetic populations from a wide geographic range. Parthenogenetic (and sexual) D. triquetrella are not monophyletic, and considerable sequence variation is present suggesting multiple transitions to parthenogenesis. However, we could not establish ancestral sexual haplotypes from our dataset. Our data suggest that some parthenogenetic clades have evolved, indicating origins of parthenogenesis before the last glacial period. Multiple transitions to parthenogenesis have taken place in Dahlica triquetrella, confirming previous hypotheses. The number of different parthenogenetic clades, haplotypes and their apparent evolutionary age, clearly show that parthenogenesis has been a very successful reproductive strategy in this species over a long period.

Caregiver Expressed Emotion and Psychiatric Symptoms in African-Americans with Schizophrenia: An Attempt to Understand the Paradoxical Relationship.

PubMed

Gurak, Kayla; Weisman de Mamani, Amy

2017-06-01

Expressed emotion (EE) is a family environmental construct that assesses how much criticism, hostility, and/or emotional over-involvement a family member expresses about a patient (Hooley, Annual Review of Clinical Psychology, 2007, 3, 329). Having high levels of EE within the family environment has generally been associated with poorer patient outcomes for schizophrenia and a range of other disorders. Paradoxically, for African-American patients, high-EE may be associated with a better symptom course (Rosenfarb, Bellack, & Aziz, Journal of Abnormal Psychology, 2006, 115, 112). However, this finding is in need of additional support and, if confirmed, clarification. In line with previous research, using a sample of 30 patients with schizophrenia and their primary caregivers, we hypothesized that having a caregiver classified as low-EE would be associated with greater patient symptom severity. We also aimed to better understand why this pattern may exist by examining the content of interviews taken from the Five-Minute Speech Sample. Results supported study hypotheses. In line with Rosenfarb et al. (2006), having a low-EE caregiver was associated with greater symptom severity in African-American patients. A content analysis uncovered some interesting patterns that may help elucidate this finding. Results of this study suggest that attempts to lower high-EE in African Americans may, in fact, be counterproductive. © 2015 Family Process Institute.

The turning point in the number of traffic fatalities: two hypotheses about changes in underlying trends.

PubMed

Brüde, Ulf; Elvik, Rune

2015-01-01

The number of traffic fatalities reached a peak in many highly motorised countries around 1970. Some previous studies have suggested that the turning point in the number of traffic fatalities was inevitable and did not reflect a change in the underlying trends influencing the number of traffic fatalities. Other studies suggest that trends in traffic growth and fatality rate changed from before to after the turning point. This paper proposes two hypotheses about the turning point in the number of traffic fatalities. One hypothesis is that the long-term trends in traffic growth and fatality rate were the same before and after the turning point. The other hypothesis is that the long-term trends in traffic growth and fatality rate were different before and after the turning point was reached, in particular that the annual percentage decline in fatality rate became greater after the turning point than before. Such a change would suggest that road safety policy became more effective. Analysis of data for six countries (Denmark, Great Britain, Netherlands, Norway, Sweden, United States) lends stronger support to the latter hypothesis than to the former. The lesson for policy makers, in particular in countries where the number of traffic fatalities is still growing, is that they should not expect a turning point to be reached without policy interventions. Copyright © 2014 Elsevier Ltd. All rights reserved.