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

The underlying meaning of stimuli: Impact on engagement of persons with dementia

PubMed Central

Cohen-Mansfield, Jiska; Thein, Khin; Dakheel-Ali, Maha; Marx, Marcia S.

2010-01-01

In a previous article, we discussed a theoretical framework asserting that a combination of stimulus attributes, person attributes and environmental attributes as well as interactions among these affect engagement with stimuli by persons with dementia (Cohen-Mansfield et al., in press). Based on this framework, we tested the impact on engagement of the personal meaning of stimuli, specifically examining work-like stimuli, stimuli based on the person’s identity, and gender role based activities. We hypothesized that having such meanings will render stimuli more engaging than stimuli without these meanings. Participants were 193 residents of 7 Maryland nursing homes. All participants had a diagnosis of dementia. Results confirmed the hypotheses, demonstrating that the meaning of the stimulus impacts engagement shown by persons with dementia. Interventions that involve objects or tasks with meaning specific to the person with dementia will be more likely to engage that person. Future research could explore more identity roles as well as other mechanisms affecting engagement. PMID:20392502

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

Oppositional identities: dissimilarities in how women and men experience parent versus professional roles.

PubMed

Hodges, Allegra J; Park, Bernadette

2013-08-01

As stereotypes of social groups undergo change, group members gain access to previously denied social and cultural roles. Although such access is desirable, to the extent that the behavior, traits, and attitudes required to succeed in a new role are in opposition to those required to do well in a still-valued old role, conflict in the self-concept may ensue. Specifically, the individual must necessarily fall short in social comparisons of the self to the ideal group member in 1 or both roles, threatening self-integrity. Examining the specific case of oppositional identities between career and mom roles, we argue that women respond to this conflict by shifting back and forth between activation of whichever identity is relevant in a given situational context in a way that men do not. This shifting of self-associations is hypothesized to deplete scarce cognitive resources, interfering with performance on a task that requires executive function capacity. In addition, to the extent the identities are viewed as trading off against one another, failure in 1 domain may be responded to by activating the alternate identity in an effort to restore self-integrity, again in a way that is not true for men. These hypotheses are explored across 4 studies, utilizing both college students in the midst of formulating--and working parents in the midst of negotiating--these identities.

Oppositional Identities: Dissimilarities in How Women and Men Experience Parent versus Professional Roles

PubMed Central

Park, Bernadette

2013-01-01

As stereotypes of social groups undergo change, group members gain access to previously denied social and cultural roles. Although such access is desirable, to the extent that the behavior, traits, and attitudes required to succeed in a new role are in opposition to those required to do well in a still-valued old role, conflict in the self-concept may ensue. Specifically, the individual must necessarily fall short in social comparisons of the self to the ideal group member in one or both roles, threatening self-integrity. Examining the specific case of oppositional identities between career and mom roles, we argue that women respond to this conflict by shifting back and forth between activation of whichever identity is relevant in a given situational context in a way that men do not. This shifting of self-associations is hypothesized to deplete scarce cognitive resources, interfering with performance on a task that requires executive function capacity. In addition, to the extent the identities are viewed as trading off against one another, failure in one domain may be responded to by activating the alternate identity in an effort to restore self-integrity, again in a way that is not true for men. These hypotheses are explored across four studies, utilizing both college students in the midst of formulating – and working parents in the midst of negotiating – these PMID:23713699

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.

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.

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.

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.

Moving away from a cultural deficit to a holistic perspective: Traditional gender role values, academic attitudes, and educational goals for Mexican descent adolescents.

PubMed

Piña-Watson, Brandy; Lorenzo-Blanco, Elma I; Dornhecker, Marianela; Martinez, Ashley J; Nagoshi, Julie L

2016-04-01

Latina/o youth lag behind Asian American and non-Latina/o White youth in many academic areas. Previous research has taken a deficit approach to understand the factors that affect academic outcomes for Latina/o youth often neglecting to highlight both the potential positive and negative contributions of gender role values. The present study took a holistic perspective to understand the affect of traditional Latina/o gender role values (i.e., marianismo, machismo, and caballerismo) on the academic attitudes and educational goals of Mexican descent youth. Structural equation models were tested to examine the associations of "positive" and "negative" gender role values on educational goals using 524 Mexican descent adolescents from a mid-sized city in southern Texas. We hypothesized that positive aspects of traditional Latina/o gender role values (i.e., "positive marianismo" and caballerismo) would be associated with more positive attitudes toward academics and higher educational goals. We further expected negative gender role values (i.e., "negative marianismo" and machismo) to have the opposite effect. Additionally, based on the theory of planned behavior and gender schema theory, academic attitudes were hypothesized to mediate the relation between gender role values and educational goals. An alternative model was tested in which educational goals mediated the relation between gender roles and academic attitudes. Results indicated that both models fit the data well, and recommendations are made for future longitudinal research aimed at disentangling the directionality of the relations in the model. Implications for research and practice are discussed. (c) 2016 APA, all rights reserved).

Elaborating on theory with middle managers' experience implementing healthcare innovations in practice.

PubMed

Birken, Sarah A; DiMartino, Lisa D; Kirk, Meredith A; Lee, Shoou-Yih D; McClelland, Mark; Albert, Nancy M

2016-01-04

The theory of middle managers' role in implementing healthcare innovations hypothesized that middle managers influence implementation effectiveness by fulfilling the following four roles: diffusing information, synthesizing information, mediating between strategy and day-to-day activities, and selling innovation implementation. The theory also suggested several activities in which middle managers might engage to fulfill the four roles. The extent to which the theory aligns with middle managers' experience in practice is unclear. We surveyed middle managers (n = 63) who attended a nursing innovation summit to (1) assess alignment between the theory and middle managers' experience in practice and (2) elaborate on the theory with examples from middle managers' experience overseeing innovation implementation in practice. Middle managers rated all of the theory's hypothesized four roles as "extremely important" but ranked diffusing and synthesizing information as the most important and selling innovation implementation as the least important. They reported engaging in several activities that were consistent with the theory's hypothesized roles and activities such as diffusing information via meetings and training. They also reported engaging in activities not described in the theory such as appraising employee performance. Middle managers' experience aligned well with the theory and expanded definitions of the roles and activities that it hypothesized. Future studies should assess the relationship between hypothesized roles and the effectiveness with which innovations are implemented in practice. If evidence supports the theory, the theory should be leveraged to promote the fulfillment of hypothesized roles among middle managers, doing so may promote innovation implementation.

Shallow cloud statistics over Tropical Western Pacific: CAM5 versus ARM Comparison

NASA Astrophysics Data System (ADS)

Chandra, A.; Zhang, C.; Klein, S. A.; Ma, H. Y.; Kollias, P.; Xie, S.

2014-12-01

The role of shallow convection in the tropical convective cloud life cycle has received increasing interest because of its sensitivity to simulate large-scale tropical disturbances such as MJO. Though previous studies have proposed several hypotheses to explain the role of shallow clouds in the convective life cycle, our understanding on the role of shallow clouds is still premature. There are more questions needs to be addressed related to the role of different cloud population, conditions favorable for shallow to deep convection transitions, and their characteristics at different stages of the convective cloud life. The present study aims to improve the understanding of the shallow clouds by documenting the role of different shallow cloud population for the Year of Tropical Convection period using Atmospheric Radiation Measurement observations at the Tropical Western Pacific Manus site. The performance of the CAM5 model to simulate shallow clouds are tested using observed cloud statistics.

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.

5S rRNA and ribosome.

PubMed

Gongadze, G M

2011-12-01

5S rRNA is an integral component of the ribosome of all living organisms. It is known that the ribosome without 5S rRNA is functionally inactive. However, the question about the specific role of this RNA in functioning of the translation apparatus is still open. This review presents a brief history of the discovery of 5S rRNA and studies of its origin and localization in the ribosome. The previously expressed hypotheses about the role of this RNA in the functioning of the ribosome are discussed considering the unique location of 5S rRNA in the ribosome and its intermolecular contacts. Based on analysis of the current data on ribosome structure and its functional complexes, the role of 5S rRNA as an intermediary between ribosome functional domains is discussed.

Toll-like receptor 2 and type 2 diabetes.

PubMed

Sepehri, Zahra; Kiani, Zohre; Nasiri, Ali Akbar; Kohan, Farhad

2016-01-01

Innate immunity plays a crucial role in the pathogenesis of type 2 diabetes and related complications. Since the toll-like receptors (TLRs) are central to innate immunity, it appears that they are important participants in the development and pathogenesis of the disease. Previous investigations demonstrated that TLR2 homodimers and TLR2 heterodimers with TLR1 or TLR6 activate innate immunity upon recognition of damage-associated molecular patterns (DAMPs). Several DAMPs are released during type 2 diabetes, so it may be hypothesized that TLR2 is significantly involved in its progression. Here, we review recent data on the important roles and status of TLR2 in type 2 diabetes and related complications.

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).

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

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.

The dynamic spillover of satisfaction between work and marriage: the role of time and mood.

PubMed

Heller, Daniel; Watson, David

2005-11-01

Previous research has indicated important linkages between work and family domains and roles. However, the nature of the dynamic spillover between job and marital satisfaction remains poorly understood. The current study tests both the concurrent and lagged associations between job and marital satisfaction at a within-individual level of analysis using a diary study of 76 fully employed, married adults. The authors further examine the mediating role of mood in this spillover process. Consistent with their hypotheses, findings indicate both a concurrent and a lagged (job to marital and marital to job) job satisfaction-marital satisfaction association at the within-subject level of analysis and lend some support for the mediating role of mood (most notably positive affect) in these associations. The authors hope these findings stimulate new research that uses more complex designs and comprehensive theoretical models to investigate work-family links. ((c) 2005 APA, all rights reserved).

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.

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.

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.

Job characteristics, flow, and performance: the moderating role of conscientiousness.

PubMed

Demerouti, Evangelia

2006-07-01

The present article aims to show the importance of positive work-related experiences within occupational health psychology by examining the relationship between flow at work (i.e., absorption, work enjoyment, and intrinsic work motivation) and job performance. On the basis of the literature, it was hypothesized that (a) motivating job characteristics are positively related to flow at work and (b) conscientiousness moderates the relationship between flow and other ratings of (in-role and out-of-role) performance. The hypotheses were tested on a sample of 113 employees from several occupations. Results of moderated structural equation modeling analyses generally supported the hypotheses. Motivating job characteristics were predictive of flow, and flow predicted in-role and extra-role performance, for only conscientious employees.

Cortico-striatal language pathways dynamically adjust for syntactic complexity: A computational study.

PubMed

Szalisznyó, Krisztina; Silverstein, David; Teichmann, Marc; Duffau, Hugues; Smits, Anja

2017-01-01

A growing body of literature supports a key role of fronto-striatal circuits in language perception. It is now known that the striatum plays a role in engaging attentional resources and linguistic rule computation while also serving phonological short-term memory capabilities. The ventral semantic and the dorsal phonological stream dichotomy assumed for spoken language processing also seems to play a role in cortico-striatal perception. Based on recent studies that correlate deep Broca-striatal pathways with complex syntax performance, we used a previously developed computational model of frontal-striatal syntax circuits and hypothesized that different parallel language pathways may contribute to canonical and non-canonical sentence comprehension separately. We modified and further analyzed a thematic role assignment task and corresponding reservoir computing model of language circuits, as previously developed by Dominey and coworkers. We examined the models performance under various parameter regimes, by influencing how fast the presented language input decays and altering the temporal dynamics of activated word representations. This enabled us to quantify canonical and non-canonical sentence comprehension abilities. The modeling results suggest that separate cortico-cortical and cortico-striatal circuits may be recruited differently for processing syntactically more difficult and less complicated sentences. Alternatively, a single circuit would need to dynamically and adaptively adjust to syntactic complexity. Copyright © 2016. Published by Elsevier Inc.

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.

On the hydration of subnanometric antifouling organosilane adlayers: a molecular dynamics simulation.

PubMed

Sheikh, Sonia; Blaszykowski, Christophe; Nolan, Robert; Thompson, Damien; Thompson, Michael

2015-01-01

The connection between antifouling and surface hydration is a fascinating but daunting question to answer. Herein, we use molecular dynamics (MD) computer simulations to gain further insight into the role of surface functionalities in the molecular-level structuration of water (surface kosmotropicity)--within and atop subnanometric organosilane adlayers that were shown in previous experimental work to display varied antifouling behavior. Our simulations support the hypothesized intimate link between surface hydration and antifouling, in particular the importance of both internal and interfacial hydrophilicity and kosmotropicity. The antifouling mechanism is also discussed in terms of surface dehydration energy and water dynamicity (lability and mobility), notably the crucial requirement for clustered water molecules to remain tightly bound for extensive periods of time--i.e. exhibit slow exchange dynamics. A substrate effect on surface hydration, which would also participate in endowing antifouling adlayers with hydrogel-like characteristics, is also proposed. In contrast, the role of adlayer flexibility, if any, is assigned a secondary role in these ultrathin structures made of short building blocks. The conclusions from this work are well in line with those previously drawn in the literature. Copyright © 2014 Elsevier Inc. All rights reserved.

A Model of In vitro Plasticity at the Parallel Fiber—Molecular Layer Interneuron Synapses

PubMed Central

Lennon, William; Yamazaki, Tadashi; Hecht-Nielsen, Robert

2015-01-01

Theoretical and computational models of the cerebellum typically focus on the role of parallel fiber (PF)—Purkinje cell (PKJ) synapses for learned behavior, but few emphasize the role of the molecular layer interneurons (MLIs)—the stellate and basket cells. A number of recent experimental results suggest the role of MLIs is more important than previous models put forth. We investigate learning at PF—MLI synapses and propose a mathematical model to describe plasticity at this synapse. We perform computer simulations with this form of learning using a spiking neuron model of the MLI and show that it reproduces six in vitro experimental results in addition to simulating four novel protocols. Further, we show how this plasticity model can predict the results of other experimental protocols that are not simulated. Finally, we hypothesize what the biological mechanisms are for changes in synaptic efficacy that embody the phenomenological model proposed here. PMID:26733856

The acoustic features of human laughter

NASA Astrophysics Data System (ADS)

Bachorowski, Jo-Anne; Owren, Michael J.

2002-05-01

Remarkably little is known about the acoustic features of laughter, despite laughter's ubiquitous role in human vocal communication. Outcomes are described for 1024 naturally produced laugh bouts recorded from 97 young adults. Acoustic analysis focused on temporal characteristics, production modes, source- and filter-related effects, and indexical cues to laugher sex and individual identity. The results indicate that laughter is a remarkably complex vocal signal, with evident diversity in both production modes and fundamental frequency characteristics. Also of interest was finding a consistent lack of articulation effects in supralaryngeal filtering. Outcomes are compared to previously advanced hypotheses and conjectures about this species-typical vocal signal.

T-kininogen induces endothelial cell proliferation.

PubMed

Pérez, Viviana; Leiva-Salcedo, Elías; Acuña-Castillo, Claudio; Aravena, Mauricio; Gómez, Christian; Sabaj, Valeria; Colombo, Alicia; Nishimura, Sumiyo; Pérez, Claudio; Walter, Robin; Sierra, Felipe

2006-03-01

Basal proliferation of endothelial cells increases with age, and this might play a role in the etiology of age-related vascular diseases, as well as angiogenesis. Serum kininogen levels increase during aging in rats and humans, and T-kininogen (T-KG) can affect proliferative homeostasis in several cell models. Both kinins and kininogens have been shown previously to be angiogenic through activation of endothelial cell proliferation, and here we show that exposure of endothelial cells to T-KG results in vigorous cell proliferation, accompanied by ERK/AKT activation. In our experiments, the proliferative response requires B1 and B2 kinin receptors, even though kinins are not released from the precursor. We hypothesize that the age-related increase in T-KG could play a significant role in the age-related dysregulation of vascular physiology and function.

Teacher role stress, satisfaction, commitment, and intentions to leave: a structural model.

PubMed

Conley, Sharon; You, Sukkyung

2009-12-01

Structural equation modeling was used to assess the plausibility of a conceptual model specifying hypothesized linkages among teachers' perceptions of the role stresses of role ambiguity, role conflict, and role overload and commitment, satisfaction, and intentions to leave their employing school. 178 teachers in four high schools in a southern coastal region of California responded to survey questions designed to capture the above constructs. Confirmatory factor analysis was used to assess whether the role-stress items fit hypothesized constructs. Structural equation modeling results indicated that satisfaction and commitment are two mediators in the role stresses-intentions to leave relationship.

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.

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

Predictors of Clinical Pain in Fibromyalgia: Examining the Role of Sleep

PubMed Central

Anderson, Ryan J.; McCrae, Christina S.; Staud, Roland; Berry, Richard B.; Robinson, Michael E.

2013-01-01

Understanding individual differences in the variability of fibromyalgia pain can help elucidate etiological mechanisms and treatment targets. Past research has shown that spatial extent of pain, negative mood, and aftersensation (pain ratings taken after experimental induction of pain) accounts for 40 to 50% of the variance in clinical pain. Poor sleep is hypothesized to have a reciprocal relationship with pain, and over 75% of individuals with fibromyalgia report disturbed sleep. We hypothesized that measures of sleep would increase the predictive ability of the clinical pain model. Measures of usual pain, spatial extent of pain, negative mood, and pain aftersensation were taken from 74 adults with fibromyalgia. Objective (actigraph) and subjective (diary) measures of sleep duration and nightly wake time were also obtained from the participants over 14 days. Hierarchical regression indicated that greater spatial extent (R2 = .26), higher aftersensation ratings (R2 = .06), and higher negative mood (R2 = .04) accounted for 36% of the variance in clinical pain (average of 14 daily pain ratings). None of the sleep variables were significant predictors of clinical pain. Results replicate previous research and suggest that spatial extent of pain, pain aftersensation, and negative mood play important roles in clinical pain, but sleep disturbance did not aid in its prediction. PMID:22381437

Coping with Peer Victimization: The Role of Children's Attributions

ERIC Educational Resources Information Center

Visconti, Kari Jeanne; Sechler, Casey M.; Kochenderfer-Ladd, Becky

2013-01-01

A social-cognitive framework was used to generate and test hypotheses regarding the role of children's causal attributions for peer victimization in predicting how they cope with such experiences. It was hypothesized that attributions would be differentially associated with coping as a function of the direction (i.e., upward, horizontal, or…

The protein kinase Mζ network as a bistable switch to store neuronal memory.

PubMed

Ogasawara, Hideaki; Kawato, Mitsuo

2010-12-31

Protein kinase Mζ (PKMζ), the brain-specific, atypical protein kinase C isoform, plays a key role in long-term maintenance of memory. This molecule is essential for long-term potentiation of the neuron and various modalities of learning such as spatial memory and fear conditioning. It is unknown, however, how PKMζ stores information for long periods of time despite molecular turnover. We hypothesized that PKMζ forms a bistable switch because it appears to constitute a positive feedback loop (PKMζ induces its local synthesis) part of which is ultrasensitive (PKMζ stimulates its synthesis through dual pathways). To examine this hypothesis, we modeled the biochemical network of PKMζ with realistic kinetic parameters. Bifurcation analyses of the model showed that the system maintains either the up state or the down state according to previous inputs. Furthermore, the model was able to reproduce a variety of previous experimental results regarding synaptic plasticity and learning, which suggested that it captures the essential mechanism for neuronal memory. We proposed in vitro and in vivo experiments that would critically examine the validity of the model and illuminate the pivotal role of PKMζ in synaptic plasticity and learning. This study revealed bistability of the PKMζ network and supported its pivotal role in long-term storage of memory.

Separable Roles for Attentional Control Sub-Systems in Reading Tasks: A Combined Behavioral and fMRI Study

PubMed Central

Ihnen, S.K.Z.; Petersen, Steven E.; Schlaggar, Bradley L.

2015-01-01

Attentional control is important both for learning to read and for performing difficult reading tasks. A previous study invoked 2 mechanisms to explain reaction time (RT) differences between reading tasks with variable attentional demands. The present study combined behavioral and neuroimaging measures to test the hypotheses that there are 2 mechanisms of interaction between attentional control and reading; that these mechanisms are dissociable both behaviorally and neuro-anatomically; and that the 2 mechanisms involve functionally separable control systems. First, RT evidence was found in support of the 2-mechanism model, corroborating the previous study. Next, 2 sets of brain regions were identified as showing functional magnetic resonance imaging blood oxygen level-dependent activity that maps onto the 2-mechanism distinction. One set included bilateral Cingulo-opercular regions and mostly right-lateralized Dorsal Attention regions (CO/DA+). This CO/DA+ region set showed response properties consistent with a role in reporting which processing pathway (phonological or lexical) was biased for a particular trial. A second set was composed primarily of left-lateralized Frontal-parietal (FP) regions. Its signal properties were consistent with a role in response checking. These results demonstrate how the subcomponents of attentional control interact with subcomponents of reading processes in healthy young adults. PMID:24275830

Relationships between sleep and addiction: the role of drug-environment conditioning.

PubMed

Berro, Laís F; Frussa-Filho, Roberto; Tufik, Sergio; Andersen, Monica L

2014-03-01

Addiction to cocaine and other amphetamine-like psychostimulants is a chronic relapsing disorder characterized by loss of control over drug taking. Sleep disturbance is common among patients in recovery from drug abuse and can precipitate relapse. It has been widely demonstrated that sleep deprivation and psychostimulants share similar neurobiological effects regarding the dopaminergic system. In addition, the persistence of a drug-environment conditioning induced by repeated psychostimulant treatment, which is deeply related to the dopaminergic neurotransmission, is thought to play a key role in the addictive cycle. In this scenario, we hypothesized that sleep deprivation is a potential detrimental factor to the extinction process of previously established drug-environment conditioning. Therefore, sleep deprivation would extend the pairing between the cocaine reinforcing effects and the environmental cues, thereby leading drug abusers to relapse. Copyright © 2014 Elsevier Ltd. All rights reserved.

Exercise collapse associated with sickle cell trait (ECAST): case report and literature review.

PubMed

Quattrone, Richard D; Eichner, E Randy; Beutler, Anthony; Adams, W Bruce; O'Connor, Francis G

2015-01-01

Sickle cell trait (SCT) has been associated with exertional collapse (ECAST) and exercise-related sudden death in athletes and military warfighters. The mechanisms underlying ECAST remain controversial in the sports medicine community. Multiple case presentations and anecdotal reports postulate the role of extraordinary exercise intensity, but other risk factors including dehydration, heat, previous exertional rhabdomyolysis, genetic cofactors, and dietary supplements have been cited as potential contributors. Others have hypothesized some of the aforementioned factors combining in a "perfect storm" to trigger ECAST with a resultant potentially fatal "metabolic crisis." This case report provides a brief review of SCT as it pertains to exercise in warfighters and athletes, identifies known and postulated risk factors associated with ECAST, and introduces the potential mechanistic role of the "double hit" as a contributor to ECAST.

Linguistic nonimmediacy and self-presentation.

PubMed

Conville, R L

1975-07-01

It has been previously shown that Ss accurately infer communicators' levels of negative effect on the basis of communicators' levels of linguistic nonimmediacy (the degree of verbal indirectness with which a communicator refers to himself or to that about which he communicates). It was hypothesized that Ss would also rely on communicators' levels of linguistic nonimmediacy for impression formation, specifically that Ss would perceive communicators using lower levels of linguistic nonimmediacy as more authoritative and as having a more positive character than communicators using higher levels of linguistic nonimmediacy. The hypothesis was partially confirmed in a study of 12 college students who rated samples of student speeches by means of McCroskey's impression formation instrument for public speakers. The results were discussed in terms of the role of language in self-presentation and the role of interpretative procedures in social interaction.

Acute lymphoblastic leukemia in a 2-year-old girl whose mother was previously diagnosed with antiphospholipid syndrome: a case report.

PubMed

Castro-Jiménez, Miguel Ángel; Cortés-Sánchez, Carlos Efraín; Rueda-Arenas, Ernesto; Tibaduiza-Buitrago, Lucy Adela

2015-04-15

The role of maternal exposures and conditions in the origin of childhood cancer has been a subject of growing interest, but current evidence is inconclusive. We present a case detected in a multicenter case-control study evaluating the association between parental risk factors and childhood acute lymphoblastic leukemia (ALL). The patient is a Colombian girl who was diagnosed with ALL-L1 when she was 2 years old. Her mother had been diagnosed with antiphospholipid syndrome before pregnancy and had also been treated with subcutaneous injections of heparin. Other potentially relevant maternal and patient exposures are also reported in this paper. We hypothesize that the maternal autoimmune disease could be a contributor in the causality network of the daughter's leukemia. However, the role of other exposures cannot be excluded.

Emulation as an Integrating Principle for Cognition

PubMed Central

Colder, Brian

2011-01-01

Emulations, defined as ongoing internal representations of potential actions and the futures those actions are expected to produce, play a critical role in directing human bodily activities. Studies of gross motor behavior, perception, allocation of attention, response to errors, interoception, and homeostatic activities, and higher cognitive reasoning suggest that the proper execution of all these functions relies on emulations. Further evidence supports the notion that reinforcement learning in humans is aimed at updating emulations, and that action selection occurs via the advancement of preferred emulations toward realization of their action and environmental prediction. Emulations are hypothesized to exist as distributed active networks of neurons in cortical and sub-cortical structures. This manuscript ties together previously unrelated theories of the role of prediction in different aspects of human information processing to create an integrated framework for cognition. PMID:21660288

Learning Hypotheses and an Associated Tool to Design and to Analyse Teaching-Learning Sequences. Special Issue

ERIC Educational Resources Information Center

Buty, Christian; Tiberghien, Andree; Le Marechal, Jean-Francois

2004-01-01

This contribution presents a tool elaborated from a theoretical framework linking epistemological, learning and didactical hypotheses. This framework lead to design teaching sequences from a socio-constructivist perspective, and is based on the role of models in physics or chemistry, and on the role of students' initial knowledge in learning…

Can theories of visual representation help to explain asymmetries in amygdala function?

PubMed

McMenamin, Brenton W; Marsolek, Chad J

2013-06-01

Emotional processing differs between the left and right hemispheres of the brain, and functional differences have been reported more specifically between the left and right amygdalae, subcortical structures heavily implicated in emotional processing. However, the empirical pattern of amygdalar asymmetries is inconsistent with extant theories of emotional asymmetries. Here we review this discrepancy, and we hypothesize that hemispheric differences in visual object processing help to explain the previously reported functional differences between the left and right amygdalae. The implication that perceptual factors play a large role in determining amygdalar asymmetries may help to explain amygdalar dysfunction in the development and maintenance of posttraumatic stress disorder.

The Kv7 Channel and Cardiovascular Risk Factors.

PubMed

Fosmo, Andreas L; Skraastad, Øyvind B

2017-01-01

Potassium channels play a pivotal role in the regulation of excitability in cells such as neurons, cardiac myocytes, and vascular smooth muscle cells. The KCNQ (Kv7) family of voltage-activated K + channels hyperpolarizes the cell and stabilizes the membrane potential. Here, we outline how Kv7 channel activity may contribute to the development of the cardiovascular risk factors such as hypertension, diabetes, and obesity. Questions and hypotheses regarding previous and future research have been raised. Alterations in the Kv7 channel may contribute to the development of cardiovascular disease (CVD). Pharmacological modification of Kv7 channels may represent a possible treatment for CVD in the future.

The Kv7 Channel and Cardiovascular Risk Factors

PubMed Central

Fosmo, Andreas L.; Skraastad, Øyvind B.

2017-01-01

Potassium channels play a pivotal role in the regulation of excitability in cells such as neurons, cardiac myocytes, and vascular smooth muscle cells. The KCNQ (Kv7) family of voltage-activated K+ channels hyperpolarizes the cell and stabilizes the membrane potential. Here, we outline how Kv7 channel activity may contribute to the development of the cardiovascular risk factors such as hypertension, diabetes, and obesity. Questions and hypotheses regarding previous and future research have been raised. Alterations in the Kv7 channel may contribute to the development of cardiovascular disease (CVD). Pharmacological modification of Kv7 channels may represent a possible treatment for CVD in the future. PMID:29259974

Dealing with Organizational Double Binds: Three-way Interactive Effects of Role Stressors and Coping on Worker Exhaustion.

PubMed

Hornung, Severin; Lampert, Bettina; Glaser, Jürgen

2016-04-01

Based on theory regarding the dynamics of organizational double binds, hypotheses were developed about interactive effects of role conflict, role ambiguity, and coping on psychological exhaustion. Hypotheses were tested in a sample of 948 civil servants employed by a government administration in Germany. The sample included 250 (26.4%) women (M age = 43.6 year, SD = 8.3) and average organizational tenure was 17.1 year (SD = 10.0). Moderated multiple regression supported the two hypothesized three-way interactions. Under conditions of high role conflict and high role ambiguity, exhaustion was lower in workers reporting high control coping than in workers reporting low control coping. Under conditions of high role conflict and high role ambiguity, worker exhaustion was more pronounced when support coping was high than when it was low. Problem-focused control coping seems crucial to maintain mental health in dealing with contradictory and unclear work role expectations. Emotion-focused support coping appears symptomatic of prolonged involvement in psychologically dysfunctional work situations that cannot otherwise be addressed. Implications are discussed in the context of growing awareness of the contradictory demands organizations impose on employees. © The Author(s) 2016.

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

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

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.

Prefrontal cortical response to conflict during semantic and phonological tasks.

PubMed

Snyder, Hannah R; Feigenson, Keith; Thompson-Schill, Sharon L

2007-05-01

Debates about the function of the prefrontal cortex are as old as the field of neuropsychology--often dated to Paul Broca's seminal work. Theories of the functional organization of the prefrontal cortex can be roughly divided into those that describe organization by process and those that describe organization by material. Recent studies of the function of the posterior, left inferior frontal gyrus (pLIFG) have yielded two quite different interpretations: One hypothesis holds that the pLIFG plays a domain-specific role in phonological processing, whereas another hypothesis describes a more general function of the pLIFG in cognitive control. In the current study, we distinguish effects of increasing cognitive control demands from effects of phonological processing. The results support the hypothesized role for the pLIFG in cognitive control, and more task-specific roles for posterior areas in phonology and semantics. Thus, these results suggest an alternative explanation of previously reported phonology-specific effects in the pLIFG.

The impact of gender-role nonconforming behavior, bullying, and social support on suicidality among gay male youth.

PubMed

Friedman, Mark S; Koeske, Gary F; Silvestre, Anthony J; Korr, Wynne S; Sites, Edward W

2006-05-01

This study hypothesized that gender-role nonconformity is associated with suicidality, and bullying mediates this relationship. Gay males retrospectively answered questions pertaining to elementary, middle, and high school. Support for the hypotheses was found. Results can help screen gay youth for suicidality and support the need for policies prohibiting harassment based on sexual orientation.

Roles of Abductive Reasoning and Prior Belief in Children's Generation of Hypotheses about Pendulum Motion

ERIC Educational Resources Information Center

Kwon, Yong-Ju; Jeong, Jin-Su; Park, Yun-Bok

2006-01-01

The purpose of the present study was to test the hypothesis that student's abductive reasoning skills play an important role in the generation of hypotheses on pendulum motion tasks. To test the hypothesis, a hypothesis-generating test on pendulum motion, and a prior-belief test about pendulum motion were developed and administered to a sample of…

Are 50-khz calls used as play signals in the playful interactions of rats? III. The effects of devocalization on play with unfamiliar partners as juveniles and as adults.

PubMed

Kisko, Theresa M; Euston, David R; Pellis, Sergio M

2015-04-01

When playing, rats emit 50-kHz calls which may function as play signals. A previous study using devocalized rats provides support for the hypothesis that 50-kHz function to promote and maintain playful interactions (Kisko et al., 2015). However, in that study, all pairs were cage mates and familiar with each other's playful tendencies that could have attenuated the role of play signals. The present study uses unfamiliar pairs to eliminate any chance for such attenuation. Four hypotheses about how 50-kHz calls could act as play signals were tested, that (1) they maintain the playful mood of the partner, (2) they are used to locate partners, (3) they attract play partners and (4) they reduce the risk of playful encounters from escalating to serious fights. Predictions arising from the first three hypotheses, tested in juveniles, were not supported, suggesting that, for juveniles, 50-kHz calls are not facilitating playful interactions as play signals. The fourth hypothesis, however, was supported in adults, but not in juveniles, in that unfamiliar adult males were more likely to escalate playful encounters into serious fights when one partner was devocalized. These findings suggest that vocalizations at most have a minor role in juvenile play but serve a more central role in modulating adult interactions between strangers, allowing for the tactical mitigation of the risk of aggression. Copyright © 2015 Elsevier B.V. All rights reserved.

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.

Gap junctions and connexin hemichannels in the regulation of haemostasis and thrombosis.

PubMed

Vaiyapuri, Sakthivel; Flora, Gagan D; Gibbins, Jonathan M

2015-06-01

Platelets are involved in the maintenance of haemostasis but their inappropriate activation leads to thrombosis, a principal trigger for heart attack and ischaemic stroke. Although platelets circulate in isolation, upon activation they accumulate or aggregate together to form a thrombus, where they function in a co-ordinated manner to prevent loss of blood and control wound repair. Previous report (1) indicates that the stability and functions of a thrombus are maintained through sustained, contact-dependent signalling between platelets. Given the role of gap junctions in the co-ordination of tissue responses, it was hypothesized that gap junctions may be present within a thrombus and mediate intercellular communication between platelets. Therefore studies were performed to explore the presence and functions of connexins in platelets. In this brief review, the roles of hemichannels and gap junctions in the control of thrombosis and haemostasis and the future directions for this research will be discussed.

If you are able to control yourself, I will trust you: the role of perceived self-control in interpersonal trust.

PubMed

Righetti, Francesca; Finkenauer, Catrin

2011-05-01

The present research tested the hypothesis that perception of others' self-control is an indicator of their trustworthiness. The authors investigated whether, in interactions between strangers as well as in established relationships, people detect another person's self-control, and whether this perception of self-control, in turn, affects trust. Results of 4 experiments supported these hypotheses. The first 2 experiments revealed that participants detected another person's trait of self-control. Experiments 3 and 4 revealed that participants also detected the temporary depletion of another person's self-control. Confirming the authors' predictions, perceived trait and state self-control, in turn, influenced people's judgment of the other person's trustworthiness. In line with previous research, these findings support the positive value of self-control for relationships and highlight the role of perceived self-control for the development of a fundamental relationship factor: trust. (c) 2011 APA, all rights reserved.

Tornado Warning Perception and Response: Integrating the Roles of Visual Design, Demographics, and Hazard Experience.

PubMed

Schumann, Ronald L; Ash, Kevin D; Bowser, Gregg C

2018-02-01

Recent advancements in severe weather detection and warning dissemination technologies have reduced, but not eliminated, large-casualty tornado hazards in the United States. Research on warning cognition and behavioral response by the public has the potential to further reduce tornado-related deaths and injuries; however, less research has been conducted in this area compared to tornado research in the physical sciences. Extant research in this vein tends to bifurcate. One branch of studies derives from classic risk perception, which investigates cognitive, affective, and sociocultural factors in relation to concern and preparation for uncertain risks. Another branch focuses on psychological, social, and cultural factors implicated in warning response for rapid onset hazards, with attention paid to previous experience and message design. Few studies link risk perceptions with cognition and response as elicited by specific examples of warnings. The present study unites risk perception, cognition, and response approaches by testing the contributions of hypothesized warning response drivers in one set of path models. Warning response is approximated by perceived fear and intended protective action as reported by survey respondents when exposed to hypothetical tornado warning scenarios. This study considers the roles of hazard knowledge acquisition, information-seeking behaviors, previous experience, and sociodemographic factors while controlling for the effects of the visual warning graphic. Findings from the study indicate the primacy of a user's visual interpretation of a warning graphic in shaping tornado warning response. Results also suggest that information-seeking habits, previous tornado experience, and local disaster culture play strong influencing roles in warning response. © 2017 Society for Risk Analysis.

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

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.

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

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.

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.

Cryo-electron microscopy structure of human peroxiredoxin-3 filament reveals the assembly of a putative chaperone.

PubMed

Radjainia, Mazdak; Venugopal, Hariprasad; Desfosses, Ambroise; Phillips, Amy J; Yewdall, N Amy; Hampton, Mark B; Gerrard, Juliet A; Mitra, Alok K

2015-05-05

Peroxiredoxins (Prxs) are a ubiquitous class of thiol-dependent peroxidases that play an important role in the protection and response of cells to oxidative stress. The catalytic unit of typical 2-Cys Prxs are homodimers, which can self-associate to form complex assemblies that are hypothesized to have signaling and chaperone activity. Mitochondrial Prx3 forms dodecameric toroids, which can further stack to form filaments, the so-called high-molecular-weight (HMW) form that has putative holdase activity. We used single-particle analysis and helical processing of electron cryomicroscopy images of human Prx3 filaments induced by low pH to generate a ∼7-Å resolution 3D structure of the HMW form, the first such structure for a 2-Cys Prx. The pseudo-atomic model reveals interactions that promote the stacking of the toroids and shows that unlike previously reported data, the structure can accommodate a partially folded C terminus. The HMW filament lumen displays hydrophobic patches, which we hypothesize bestow holdase activity. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

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

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

Structure-based design of Trifarotene (CD5789), a potent and selective RARγ agonist for the treatment of acne.

PubMed

Thoreau, Etienne; Arlabosse, Jean-Marie; Bouix-Peter, Claire; Chambon, Sandrine; Chantalat, Laurent; Daver, Sébastien; Dumais, Laurence; Duvert, Gwenaëlle; Feret, Angélique; Ouvry, Gilles; Pascau, Jonathan; Raffin, Catherine; Rodeville, Nicolas; Soulet, Catherine; Tabet, Samuel; Talano, Sandrine; Portal, Thibaud

2018-06-01

Retinoids have a dominant role in topical acne therapy and to date, only RARβ and RARγ dual agonists have reached the market. Given the tissue distribution of RAR isoforms, it was hypothesized that developing RARγ -selective agonists could yield a new generation of topical acne treatments that would increase safety margins while maintaining the robust efficacy of previous drugs. Structural knowledge derived from the X-ray structure of known γ-selective CD437, suggested the design of a novel triaryl series of agonists which was optimized and ultimately led to the discovery of Trifarotene/CD5789. Copyright © 2018 Elsevier Ltd. All rights reserved.

Yellow fever in Brazil: thoughts and hypotheses on the emergence in previously free areas.

PubMed

Vasconcelos, Pedro Fernando da Costa

2010-12-01

This article describes and discusses factors associated to the reemergence of yellow fever and its transmission dynamics in the states of São Paulo (Southeastern Brazil) and Rio Grande do Sul (Southern) during 2008 and 2009. The following factors have played a pivotal role for the reemergence of yellow fever in these areas: large susceptible human population; high prevalence of vectors and primary hosts (non-human primates); favorable climate conditions, especially increased rainfall; emergence of a new genetic lineage; and circulation of people and/or monkeys infected by virus. There is a need for an effective surveillance program to prevent the reemergence of yellow fever in other Brazilian states.

Congruent biogeographical disjunctions at a continent-wide scale: Quantifying and clarifying the role of biogeographic barriers in the Australian tropics.

PubMed

Edwards, Robert D; Crisp, Michael D; Cook, Dianne H; Cook, Lyn G

2017-01-01

To test whether novel and previously hypothesized biogeogaphic barriers in the Australian Tropics represent significant disjunction points or hard barriers, or both, to the distribution of plants. Australian tropics: Australian Monsoon Tropics and Australian Wet Tropics. The presence or absence of 6,861 plant species was scored across 13 putative biogeographic barriers in the Australian Tropics, including two that have not previously been recognised. Randomizations of these data were used to test whether more species showed disjunctions (gaps in distribution) or likely barriers (range limits) at these points than expected by chance. Two novel disjunctions in the Australian Tropics flora are identified in addition to eleven putative barriers previously recognized for animals. Of these, eleven disjunction points (all within the Australian Monsoon Tropics) were found to correspond to range-ending barriers to a significant number of species, while neither of the two disjunctions found within the Australian Wet Tropics limited a significant number of species' ranges. Biogeographic barriers present significant distributional limits to native plant species in the Australian Monsoon Tropics but not in the Australian Wet Tropics.

Learning by Reading for Robust Reasoning in Intelligent Agents

DTIC Science & Technology

2018-04-24

SUPPLEMENTARY NOTES 14. ABSTRACT Our hypotheses are that analogical processing plays multiple roles in enabling machines to learn by reading, and that...systems). Our overall hypotheses are that analogical processing plays multiple roles in learning by reading, and that qualitative representations provide...from reading this text? Narrative function can be seen as a kind of communication act, but the idea goes a bit beyond that. Communication acts are

Inhibition or Compensation? A Multidimensional Comparison of Reading Processes in Dutch and English

ERIC Educational Resources Information Center

Stevenson, Marie; Schoonen, Rob; de Glopper, Kees

2007-01-01

This study examined two competing hypotheses about second language reading processes: the inhibition hypothesis and the compensation hypothesis. Although the ideas expressed in these hypotheses have been reiterated in the literature, previous to this study, they had seldom been investigated systematically. The inhibition hypothesis states that in…

The Pathways from Parents' Marital Quality to Adolescents' School Adjustment in South Korea

ERIC Educational Resources Information Center

Jeong, Yu-Jin; Chun, Young-Ju

2010-01-01

This study tested the hypothesized pathways from parents' marital quality to Korean adolescents' school adjustment through the perception of self and parent-child relations. Based on previous literature and two major family theories, the authors hypothesized a path model to explain the process of how parents' marital quality influenced school…

Culture-specific patterns in the prediction of life satisfaction: roles of emotion, relationship quality, and self-esteem.

PubMed

Kang, Sun-Mee; Shaver, Phillip R; Sue, Stanley; Min, Kyung-Hwan; Jing, Hauibin

2003-12-01

This study was conducted to explore the culture-specific roles of emotion, relationship quality, and self-esteem in determining life satisfaction. It was hypothesized that maintaining good interpersonal relationships would make individuals in collectivistic cultures not only feel good about their lives but also feel better about themselves. Furthermore, two emotion variables--emotional expression and emotion differentiation--were proposed as possible determinants of relationship quality. It was hypothesized that emotional expressiveness would be more important for maintaining good interpersonal relationships in individualistic societies but emotion differentiation would be more important in collectivistic cultures. These hypotheses were tested with Euro-American, Asian American, Korean, and Chinese groups using multigroup analyses in a structural equation model. Results supported all proposed hypotheses and indicated that emotion differentiation contributes to maintaining good interpersonal relationships in collectivistic cultures, which contributes to self-esteem and satisfaction with life.

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.

Research priorities: women in Africa.

PubMed

Okeyo, A P

1979-01-01

In December 1979, an Expert Meeting on Research and Data Collection on Women and Development was convened in Nairobi for the purpose of defining research priorities and methodological approaches for studying the role of African women in development. After reviewing current literature relevant to the subject matter, the participants developed a number of hypotheses regarding the impact of development activities on the role and status of women, and recommended that these hypotheses be tested in future reserach. In general, agrarian reform, mechanization of agriculture, the introduction of cash cropping, and modernization were hypothesized as having a negative impact on the role, status, productive activities, and nutritional standards of women. Other hypotheses stated that development programs and agricultural extension services tended to neglect women. Recommended research methodologies include: 1) efforts to involve the community members in the development and implementation of research projects undertaken in their communities; 2) increased use of local experts and community members in data collection; and 3) interdisciplinary collaboration. The participants also recommended that each country compile a statistical profile on the women in their countries. The profiles should include comparable information on: 1) fertility; 2) educational levels, employment status, and income levels for women; 3) household composition; and 4) types of services available to women.

Emotion Dysregulation Mediates the Relation between Mindfulness and Rejection Sensitivity.

PubMed

Velotti, Patrizia; Garofalo, Carlo; Bizzi, Fabiola

2015-09-01

The role of rejection sensitivity (RS; the tendency to anxiously expect, readily perceive, and overreact to implied or overt interpersonal rejection) in psychopathology has mainly been studied with regard to borderline personality disorder (BPD). In the present study, we first sought to extend previous evidence of heightened RS in a clinical group with psychiatric disorders other than BPD, when compared with a community sample. Then, we tested whether emotion dysregulation and mindfulness were associated with RS in both sample, further hypothesizing that emotion dysregulation would mediate the relation between mindfulness deficits and RS. We adopted a cross-sectional design involving 191 psychiatric patients and 277 community participants (total N=468). All participants completed the Rejection Sensitivity Questionnaire, the Five Facet Mindfulness Questionnaire, and the Difficulties in Emotion Regulation Scale. Our hypotheses were supported, with psychiatric patients reporting greater levels of rejection sensitivity and emotion dysregulation, and lower level of mindfulness. Mindfulness deficits and emotion dysregulation explained a significant amount of variance in RS, in both samples. Finally, bootstrap analyses revealed that mindfulness deficits played an indirect effect on RS through the mediating role of emotion dysregulation. In particular, two different patterns emerged. Among psychiatric patients, an impairment in the ability to assume a non-judgmental stance towards own thoughts and feelings was related to RS through the mediation of limited access to emotion regulation strategies. Conversely, in the community sample, overall emotion dysregulation mediated the effect of lack of attention and awareness for present activities and experience on RS. Longitudinal studies could help in delineating etiological models of RS, and the joint role of deficits in mindfulness and emotion regulation should inform treatment programs.

The role of domain expertise and judgment in dealing with unexpected events

NASA Astrophysics Data System (ADS)

Kochan, Janeen Adrion

Unexpected events, particularly those creating surprise, interrupt ongoing mental and behavioral processes, creating an increased potential for unwanted outcomes to the situation. Human reactions to unexpected events vary. One can hypothesize a number of reasons for this variation, including level of domain expertise, previous experience with similar events, emotional connotation, and the contextual surround of the event. Whereas interrupting ongoing activities and focusing attention temporarily on a surprising event may be a useful evolutionary response to a threatening situation, the same process may be maladaptive in today's highly dynamic world. The purpose of this study was to investigate how different aspects of expertise affected one's ability to detect and react to an unexpected event. It was hypothesized that there were two general types of expertise, domain expertise and judgment (Hammond, 2000), which influenced one's performance on dealing with an unexpected event. The goal of the research was to parse out the relative contribution of domain expertise, so the role of judgment could be revealed. The research questions for this study were: (a) Can we identify specific knowledges and skills which enhance one's ability to deal with unexpected events? (b) Are these skills "automatically" included in domain expertise? (c) How does domain expertise improve or deter one's reaction and response to unexpected events? (d) What role does judgment play in responding to surprise? The general hypothesis was that good judgment would influence the process of surprise at different stages and in different ways than would domain expertise. The conclusions from this research indicated that good judgment had a significant positive effect in helping pilots deal with unexpected events. This was most pronounced when domain expertise was low.

Complex and changing patterns of natural selection explain the evolution of the human hip.

PubMed

Grabowski, Mark; Roseman, Charles C

2015-08-01

Causal explanations for the dramatic changes that occurred during the evolution of the human hip focus largely on selection for bipedal function and locomotor efficiency. These hypotheses rest on two critical assumptions. The first-that these anatomical changes served functional roles in bipedalism-has been supported in numerous analyses showing how postcranial changes likely affected locomotion. The second-that morphological changes that did play functional roles in bipedalism were the result of selection for that behavior-has not been previously explored and represents a major gap in our understanding of hominin hip evolution. Here we use evolutionary quantitative genetic models to test the hypothesis that strong directional selection on many individual aspects of morphology was responsible for the large differences observed across a sample of fossil hominin hips spanning the Plio-Pleistocene. Our approach uses covariance among traits and the differences between relatively complete fossils to estimate the net selection pressures that drove the major transitions in hominin hip evolution. Our findings show a complex and changing pattern of natural selection drove hominin hip evolution, and that many, but not all, traits hypothesized to play functional roles in bipedalism evolved as a direct result of natural selection. While the rate of evolutionary change for all transitions explored here does not exceed the amount expected if evolution was occurring solely through neutral processes, it was far above rates of evolution for morphological traits in other mammalian groups. Given that stasis is the norm in the mammalian fossil record, our results suggest that large shifts in the adaptive landscape drove hominin evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

The Relation of Pro-Sociality to Self-Esteem: The Mediational Role of Quality of Friendships.

PubMed

Zuffianò, Antonio; Eisenberg, Nancy; Alessandri, Guido; Luengo Kanacri, Bernadette Paula; Pastorelli, Concetta; Milioni, Michela; Caprara, Gian Vittorio

2016-02-01

The present longitudinal study examined the role of quality of friendship in mediating the relation of pro-sociality to self-esteem over time. Participants were 424 Italian young adults (56% females) assessed at two waves (M(age) = 21.1 at Time 1; M(age) = 25 at Time 2). An autoregressive cross-lagged panel model was used to test the mediational model. Self- and friend-report measures of pro-sociality, quality of friendship, and self-esteem were included in the analyses. Results were in line with the hypothesized paths, with quality of friendship mediating the relation of pro-sociality to later self-esteem above and beyond its high stability. Self-esteem, in turn, predicted pro-sociality 4 years later. Overall, the present findings support the potential benefits of behaving pro-socially for an actor in terms of increased perceived self-worth and also expand previous work by outlining the specific mediational role of the quality of friendships. The theoretical and practical implications of these results are discussed. © 2014 Wiley Periodicals, Inc.

Polarised Clathrin-Mediated Endocytosis of EGFR During Chemotactic Invasion

PubMed Central

Mutch, Laura Jane; Howden, Jake Davey; Jenner, Emma Poppy Louise; Poulter, Natalie Sarah; Rappoport, Joshua Zachary

2014-01-01

Directed cell migration is critical for numerous physiological processes including development and wound healing. However chemotaxis is also exploited during cancer progression. Recent reports have suggested links between vesicle trafficking pathways and directed cell migration. Very little is known about the potential roles of endocytosis pathways during metastasis. Therefore we performed a series of studies employing a previously characterised model for chemotactic invasion of cancer cells to assess specific hypotheses potentially linking endocytosis to directed cell migration. Our results demonstrate that clathrin-mediated endocytosis is indispensable for epidermal growth factor (EGF) directed chemotactic invasion of MDA-MB-231 cells. Conversely, caveolar endocytosis is not required in this mode of migration. We further found that chemoattractant receptor (EGFR) trafficking occurs by clathrin-mediated endocytosis and is polarised towards the front of migrating cells. However, we found no role for clathrin-mediated endocytosis in focal adhesion disassembly in this migration model. Thus, this study has characterised the role of endocytosis during chemotactic invasion and has identified functions mechanistically linking clathrin-mediated endocytosis to directed cell motility. PMID:24921075

Role of inflammasomes in inflammatory autoimmune rheumatic diseases.

PubMed

Yi, Young-Su

2018-01-01

Inflammasomes are intracellular multiprotein complexes that coordinate anti-pathogenic host defense during inflammatory responses in myeloid cells, especially macrophages. Inflammasome activation leads to activation of caspase-1, resulting in the induction of pyroptosis and the secretion of pro-inflammatory cytokines including interleukin (IL)-1β and IL-18. Although the inflammatory response is an innate host defense mechanism, chronic inflammation is the main cause of rheumatic diseases, such as rheumatoid arthritis (RA), systemic lupus erythematosus (SLE), ankylosing spondylitis (AS), and Sjögren's syndrome (SS). Since rheumatic diseases are inflammatory/autoimmune disorders, it is reasonable to hypothesize that inflammasomes activated during the inflammatory response play a pivotal role in development and progression of these diseases. Indeed, previous studies have provided important observations that inflammasomes are actively involved in the pathogenesis of inflammatory/autoimmune rheumatic diseases. In this review, we summarize the current knowledge on several types of inflammasomes during macrophage-mediated inflammatory responses and discuss recent research regarding the role of inflammasomes in the pathogenesis of inflammatory/autoimmune rheumatic diseases. This avenue of research could provide new insights for the development of promising therapeutics to treat inflammatory/autoimmune rheumatic diseases.

Scale-dependent mechanisms of habitat selection for a migratory passerine: an experimental approach

USGS Publications Warehouse

Donovan, Therese M.; Cornell, Kerri L.

2010-01-01

Habitat selection theory predicts that individuals choose breeding habitats that maximize fitness returns on the basis of indirect environmental cues at multiple spatial scales. We performed a 3-year field experiment to evaluate five alternative hypotheses regarding whether individuals choose breeding territories in heterogeneous landscapes on the basis of (1) shrub cover within a site, (2) forest land-cover pattern surrounding a site, (3) conspecific song cues during prebreeding settlement periods, (4) a combination of these factors, and (5) interactions among these factors. We tested hypotheses with playbacks of conspecific song across a gradient of landscape pattern and shrub density and evaluated changes in territory occupancy patterns in a forest-nesting passerine, the Black-throated Blue Warbler (Dendroica caerulescens). Our results support the hypothesis that vegetation structure plays a primary role during presettlement periods in determining occupancy patterns in this species. Further, both occupancy rates and territory turnover were affected by an interaction between local shrub density and amount of forest in the surrounding landscape, but not by interactions between habitat cues and social cues. Although previous studies of this species in unfragmented landscapes found that social postbreeding song cues played a key role in determining territory settlement, our prebreeding playbacks were not associated with territory occupancy or turnover. Our results suggest that in heterogeneous landscapes during spring settlement, vegetation structure may be a more reliable signal of reproductive performance than the physical location of other individuals.

From socially prescribed perfectionism to problematic use of internet communicative services: the mediating roles of perceived social support and the fear of negative evaluation.

PubMed

Casale, Silvia; Fioravanti, Giulia; Flett, Gordon L; Hewitt, Paul L

2014-12-01

The present study developed and tested a model that explains how people who believe that others have unrealistically high standards and exert pressure on them to be perfect (that is, people high in socially prescribed perfectionism) develop a problematic use of internet communicative services (GPIU). Following the perfectionism social disconnection model and previous evidence about the role that the online environment might play in the development of problematic internet use, low reported social support and the fear of negative evaluations in face to face interactions were hypothesized to mediate the association between socially prescribed perfectionism and GPIU. A sample of 465 undergraduate students was recruited (240 F; mean age 21.91+2.23years), and the hypotheses were tested through structural equation modeling separately for men and women. Among men, the association between SPP and GPIU was fully mediated by the fear of being negatively evaluated and the perception of low social support. For women, we found a partially mediated model in which SPP affected GPIU indirectly through the fear of negative evaluations. The presence of a direct effect of SPP on GPIU was also found. Moreover, perceived social support was not found to be a significant mediator among women. The findings suggest that problematic use of internet communicative services might be, at least in part, a defensive response to extreme social evaluation pressures. Copyright © 2014 Elsevier Ltd. 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

Alternative Splicing of Four Trafficking Genes Regulates Myofiber Structure and Skeletal Muscle Physiology.

PubMed

Giudice, Jimena; Loehr, James A; Rodney, George G; Cooper, Thomas A

2016-11-15

During development, transcriptional and post-transcriptional networks are coordinately regulated to drive organ maturation. Alternative splicing contributes by producing temporal-specific protein isoforms. We previously found that genes undergoing splicing transitions during mouse postnatal heart development are enriched for vesicular trafficking and membrane dynamics functions. Here, we show that adult trafficking isoforms are also expressed in adult skeletal muscle and hypothesize that striated muscle utilizes alternative splicing to generate specific isoforms required for function of adult tissue. We deliver morpholinos into flexor digitorum brevis muscles in adult mice to redirect splicing of four trafficking genes to the fetal isoforms. The splicing switch results in multiple structural and functional defects, including transverse tubule (T-tubule) disruption and dihydropyridine receptor alpha (DHPR) and Ryr1 mislocalization, impairing excitation-contraction coupling, calcium handling, and force generation. The results demonstrate a previously unrecognized role for trafficking functions in adult muscle tissue homeostasis and a specific requirement for the adult splice variants. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Heat stress enhances LTM formation in Lymnaea: role of HSPs and DNA methylation.

PubMed

Sunada, Hiroshi; Riaz, Hamza; de Freitas, Emily; Lukowiak, Kai; Swinton, Cayley; Swinton, Erin; Protheroe, Amy; Shymansky, Tamila; Komatsuzaki, Yoshimasa; Lukowiak, Ken

2016-05-01

Environmentally relevant stressors alter the memory-forming process in Lymnaea following operant conditioning of aerial respiration. One such stressor is heat. Previously, we found that following a 1 h heat shock, long-term memory (LTM) formation was enhanced. We also had shown that the heat stressor activates at least two heat shock proteins (HSPs): HSP40 and HSP70. Here, we tested two hypotheses: (1) the production of HSPs is necessary for enhanced LTM formation; and (2) blocking DNA methylation prevents the heat stressor-induced enhancement of LTM formation. We show here that the enhancing effect of the heat stressor on LTM formation occurs even if snails experienced the stressor 3 days previously. We further show that a flavonoid, quercetin, which inhibits HSP activation, blocks the enhancing effect of the heat stressor on LTM formation. Finally, we show that injection of a DNA methylation blocker, 5-AZA, before snails experience the heat stressor prevents enhancement of memory formation. © 2016. Published by The Company of Biologists Ltd.

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.

A survey of role stress, coping and health in Australian and New Zealand hospital nurses.

PubMed

Chang, Esther M L; Bidewell, John W; Huntington, Annette D; Daly, John; Johnson, Amanda; Wilson, Helen; Lambert, Vicki A; Lambert, Clinton E

2007-11-01

Previous research has identified international and cultural differences in nurses' workplace stress and coping responses. We hypothesised an association between problem-focused coping and improved health, emotion-focused coping with reduced health, and more frequent workplace stress with reduced health. Test the above hypotheses with Australian and New Zealand nurses, and compare Australian and New Zealand nurses' experience of workplace stress, coping and health status. Three hundred and twenty-eight New South Wales (NSW) and 190 New Zealand (NZ) volunteer acute care hospital nurses (response rate 41%) from randomly sampled nurses. Postal survey consisting of a demographic questionnaire, the Nursing Stress Scale, the WAYS of Coping Questionnaire and the SF-36 Health Survey Version 2. Consistent with hypotheses, more frequent workplace stress predicted lower physical and mental health. Problem-focused coping was associated with better mental health. Emotion-focused coping was associated with reduced mental health. Contrary to hypotheses, coping styles did not predict physical health. NSW and NZ scored effectively the same on sources of workplace stress, stress coping methods, and physical and mental health when controlling for relevant variables. Results suggest mental health benefits for nurses who use problem-solving to cope with stress by addressing the external source of the stress, rather than emotion-focused coping in which nurses try to control or manage their internal response to stress. Cultural similarities and similar hospital environments could account for equivalent findings for NSW and NZ.

EVALUATION OF EXPOSURE MEASUREMENT METHODS AND APPROACHES FOR THE NATIONAL CHILDREN'S STUDY

EPA Science Inventory

Several hypotheses have been proposed for the National Children's Study to examine the role of environmental exposures to chemical pollutants in health outcomes including asthma and impaired neurobehaviorial or neurocognitive function. To address these hypotheses, it will be nec...

Opting Out and Buying Out: Wives’ Earnings and Housework Time

PubMed Central

Killewald, Alexandra

2011-01-01

It has been proposed that the negative association between wives’ earnings and their time in housework is due to greater outsourcing of household labor by households with high-earning wives, but this hypothesis has not been tested directly. In a sample of dual-earner married couples in the Consumption and Activities Mail Survey of the Health and Retirement Study (N = 796), use of market substitutes for women’s housework was found to be only weakly associated with wives’ time cooking and cleaning. Furthermore, expenditures on market substitutes explain less than 15% of the earnings–housework time relationship. This suggests that use of market substitutes plays a smaller role in explaining variation in wives’ time in household labor than has previously been hypothesized. PMID:22053115

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.

Functions of graphemic and phonemic codes in visual word-recognition.

PubMed

Meyer, D E; Schvaneveldt, R W; Ruddy, M G

1974-03-01

Previous investigators have argued that printed words are recognized directly from visual representations and/or phonological representations obtained through phonemic recoding. The present research tested these hypotheses by manipulating graphemic and phonemic relations within various pairs of letter strings. Ss in two experiments classified the pairs as words or nonwords. Reaction times and error rates were relatively small for word pairs (e.g., BRIBE-TRIBE) that were both graphemically, and phonemically similar. Graphemic similarity alone inhibited performance on other word pairs (e.g., COUCH-TOUCH). These and other results suggest that phonological representations play a significant role in visual word recognition and that there is a dependence between successive phonemic-encoding operations. An encoding-bias model is proposed to explain the data.

An integrative model linking feedback environment and organizational citizenship behavior.

PubMed

Peng, Jei-Chen; Chiu, Su-Fen

2010-01-01

Past empirical evidence has suggested that a positive supervisor feedback environment may enhance employees' organizational citizenship behavior (OCB). In this study, we aim to extend previous research by proposing and testing an integrative model that examines the mediating processes underlying the relationship between supervisor feedback environment and employee OCB. Data were collected from 259 subordinate-supervisor dyads across a variety of organizations in Taiwan. We used structural equation modeling to test our hypotheses. The results demonstrated that supervisor feedback environment influenced employees' OCB indirectly through (1) both positive affective-cognition and positive attitude (i.e., person-organization fit and organizational commitment), and (2) both negative affective-cognition and negative attitude (i.e., role stressors and job burnout). Theoretical and practical implications are discussed.

The role of the CN vibration in the activated dynamics of LiNC<−>LiCN isomerization in an argon solvent at high temperatures.

PubMed

Garcia-Muller, Pablo L; Hernandez, Rigoberto; Benito, R M; Borondo, F

2014-08-21

The isomerization between CN-Li and Li-CN in an argon bath provides a paradigmatic example of a reaction in a solvent with tunable coupling. In previous work, we found that the rates exhibited a turnover with the density of the argon bath in the limit that the CN bond was held fixed [P. L. Garcia-Muller, R. Hernandez, R. M. Benito, and F. Borondo, J. Chem. Phys. 137, 204301 (2012)]. Here, we report the effect of the CN bond vibration on the dynamics and the persistence of the turnover. As hypothesized earlier, the CN bond is indeed weakly coupled with the reaction path despite the presence of the argon cage.

Genetic structure and breeding system of a rare understory herb, Dysosma versipellis (Berberidaceae), from temperate deciduous forests in China.

PubMed

Guan, Bi-Cai; Fu, Cheng-Xing; Qiu, Ying-Xiong; Zhou, Shi-Liang; Comes, Hans Peter

2010-01-01

To evaluate the role of Quaternary refugial isolation in allopatric (incipient) speciation of East Asian temperate forest biotas, we analyzed amplified fragment length polymorphisms (AFLPs) and the breeding system in Dysosma versipellis. The study revealed that D. versipellis is mostly self-incompatible, genetically highly subdivided and depauperate at the population level (e.g., Φ(ST) = 0.572/H(E) = 0.083), and characterized by a low pollen-to-seed migration ratio (r ≈ 4.0). The latter outcome likely reflects limited pollen flow in a low-seed disperser whose hypothesized "sapromyophilous" flowers undergo scarce, inefficient, and likely specialized cross-pollination by small Anoplodera beetles, rather than carrion flies as assumed previously. In consequence, fruit set in D. versipellis was strongly pollen-limited. Our AFLP data support the hypothesis of a long-standing cessation of gene flow between western and central eastern populations, consistent with previous chloroplast DNA data. This phylogeographic pattern supports the role of the Sichuan Basin as a floristic boundary separating the Sino-Himalayan vs. Sino-Japanese Forest subkingdoms. Our genetic data of D. versipellis also imply that temperate deciduous forest elements to the west and the east of this basin responded differently to Quaternary climate change, which may have triggered or is leading to allopatric (incipient) speciation.

The role of spatial memory and frames of reference in the precision of angular path integration.

PubMed

Arthur, Joeanna C; Philbeck, John W; Kleene, Nicholas J; Chichka, David

2012-09-01

Angular path integration refers to the ability to maintain an estimate of self-location after a rotational displacement by integrating internally-generated (idiothetic) self-motion signals over time. Previous work has found that non-sensory inputs, namely spatial memory, can play a powerful role in angular path integration (Arthur et al., 2007, 2009). Here we investigated the conditions under which spatial memory facilitates angular path integration. We hypothesized that the benefit of spatial memory is particularly likely in spatial updating tasks in which one's self-location estimate is referenced to external space. To test this idea, we administered passive, non-visual body rotations (ranging 40°-140°) about the yaw axis and asked participants to use verbal reports or open-loop manual pointing to indicate the magnitude of the rotation. Prior to some trials, previews of the surrounding environment were given. We found that when participants adopted an egocentric frame of reference, the previously-observed benefit of previews on within-subject response precision was not manifested, regardless of whether remembered spatial frameworks were derived from vision or spatial language. We conclude that the powerful effect of spatial memory is dependent on one's frame of reference during self-motion updating. Copyright © 2012 Elsevier B.V. All rights reserved.

Genetic evidence of intercontinental movement of avian influenza in a migratory bird: The northern pintail (Anas acuta)

USGS Publications Warehouse

Koehler, A.V.; Pearce, J.M.; Flint, Paul L.; Franson, J.C.; Ip, Hon S.

2008-01-01

The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses confirmed the genetic divergence between Asian and North American strains of LPAI, but also suggested inter-continental virus exchange and at a higher frequency than previously documented. In 38 isolates from Alaska, nearly half (44.7%) had at least one gene segment more closely related to Asian than to North American strains of LPAI. Additionally, sequences of several Asian LPAI isolates from GenBank clustered more closely with North American northern pintail isolates than with other Asian origin viruses. Our data support the role of wild birds in the intercontinental transfer of influenza viruses, and reveal a higher degree of transfer in Alaska than elsewhere in North America. ?? 2008 The Authors.

Genetic evidence of intercontinental movement of avian influenza in a migratory bird: the northern pintail (Anas acuta).

PubMed

Koehler, Anson V; Pearce, John M; Flint, Paul L; Franson, J Christian; Ip, Hon S

2008-11-01

The role of migratory birds in the movement of the highly pathogenic (HP) avian influenza H5N1 remains a subject of debate. Testing hypotheses regarding intercontinental movement of low pathogenic avian influenza (LPAI) viruses will help evaluate the potential that wild birds could carry Asian-origin strains of HP avian influenza to North America during migration. Previous North American assessments of LPAI genetic variation have found few Asian reassortment events. Here, we present results from whole-genome analyses of LPAI isolates collected in Alaska from the northern pintail (Anas acuta), a species that migrates between North America and Asia. Phylogenetic analyses confirmed the genetic divergence between Asian and North American strains of LPAI, but also suggested inter-continental virus exchange and at a higher frequency than previously documented. In 38 isolates from Alaska, nearly half (44.7%) had at least one gene segment more closely related to Asian than to North American strains of LPAI. Additionally, sequences of several Asian LPAI isolates from GenBank clustered more closely with North American northern pintail isolates than with other Asian origin viruses. Our data support the role of wild birds in the intercontinental transfer of influenza viruses, and reveal a higher degree of transfer in Alaska than elsewhere in North America.

THE ROLE OF CYTOKINES IN UBD PROMOTER REGULATION AND MALLORY-DENK BODY-LIKE AGGRESOMES

PubMed Central

Oliva, Joan; Bardag-Gorce, Fawzia; Lin, Andrew; French, Barbara.A; French, Samuel W.

2010-01-01

Mallory-Denk bodies (MDBs) are found in chronic liver diseases. Previous studies showed that Diethyl-1, 4-dihydro-2,4,6,-trimethyl-3,5-pyridinedicarboxylate (DDC) induced formation of MDBs and the up regulation of UbD expression in mouse liver. UbD is a protein over expressed in hepatocellular carcinomas. It is a potential preneoplastic marker in the mouse. It is hypothesized that inflammatory cytokines play a critical role in UbD up regulation and MDB formation. TNFa and IFNg treatment of HCC cell line Hepa 1–6, induced the expression of UbD and the expression of genes coding for the immunoproteasome (LMP2, LMP7, and MECL-1 subunits). TNFa and IFNg induced the activity of the UbD promoter, using a luciferase assay. The co-treatment with TNFa and IFNg induced the activity of the UbD promoter through an Interferon Sequence Responsive Element (ISRE). In addition, long term treatment with TNFa and IFNg induced the formation of MDB-like aggresomes in Hepa 1–6 cells, which emphasizes the role of inflammation in the formation of MDBs leading to the formation of liver tumors, in the mouse. Identifying the mechanism that regulates gene expression of UbD supports the hypothesis that down regulation of UbD and the proinflammatory gene expression would prevent MDBs and HCC formation. Previous studies indicate that S-adenosylmethionine or betaine prevented IFNg induced UbD and MDB formation. PMID:20433827

Influence of some psychosocial factors on mobbing and its consequences among employees working with people with intellectual disabilities.

PubMed

Figueiredo-Ferraz, Hugo; Gil-Monte, Pedro R; Grau-Alberola, Ester; Llorca-Pellicer, Marta; García-Juesas, Juan A

2012-09-01

The problem of mobbing has attracted a great deal of attention over the past few years. This concern has increased the study of the phenomena, which has resulted in many scientific publications. Mobbing has been characterized as an emerging risk at work. The aim of this study was to analyse the influence of some psychosocial factors at work - role clarity, interpersonal conflicts and social support - on mobbing and its consequences - that is, inclination towards absenteeism and psychosomatic disorders. The sample included 422 employees working with people with intellectual disabilities. Structural equation modelling (SEM) was used to test the hypotheses. The Hypothesized model showed an adequate fit to data, and all hypothesized relationships were significant. The results of this study provide support for the mediator role of mobbing in the relationship between high role ambiguity, low social support and high interpersonal conflicts and psychosomatic disorders and inclination towards absenteeism. © 2012 Blackwell Publishing Ltd.

Sleep restores behavioral plasticity to Drosophila mutants

PubMed Central

Dissel, Stephane; Angadi, Veena; Kirszenblat, Leonie; Suzuki, Yasuko; Donlea, Jeff; Klose, Markus; Koch, Zachary; English, Denis; Winsky-Sommerer, Raphaelle; van Swinderen, Bruno; Shaw, Paul J.

2015-01-01

SUMMARY Given the role that sleep plays in modulating plasticity, we hypothesized that increasing sleep would restore memory to canonical memory mutants without specifically rescuing the causal molecular-lesion. Sleep was increased using three independent strategies: activating the dorsal Fan Shaped Body (FB), increasing the expression of Fatty acid binding protein (dFabp) or by administering the GABA-A agonist 4,5,6,7-tetrahydroisoxazolo-[5,4-c]pyridine-3-ol (THIP). Short-term memory (STM) or Long-term memory (LTM) was evaluated in rutabaga (rut) and dunce (dnc) mutants using Aversive Phototaxic Suppression (APS) and courtship conditioning. Each of the three independent strategies increased sleep and restored memory to rut and dnc mutants. Importantly, inducing sleep also reverses memory defects in a Drosophila model of Alzheimer’s disease. Together these data demonstrate that sleep plays a more fundamental role in modulating behavioral plasticity than previously appreciated and suggests that increasing sleep may benefit patients with certain neurological disorders. PMID:25913403

A genome-wide approach accounting for body mass index identifies genetic variants influencing fasting glycemic traits and insulin resistance.

PubMed

Manning, Alisa K; Hivert, Marie-France; Scott, Robert A; Grimsby, Jonna L; Bouatia-Naji, Nabila; Chen, Han; Rybin, Denis; Liu, Ching-Ti; Bielak, Lawrence F; Prokopenko, Inga; Amin, Najaf; Barnes, Daniel; Cadby, Gemma; Hottenga, Jouke-Jan; Ingelsson, Erik; Jackson, Anne U; Johnson, Toby; Kanoni, Stavroula; Ladenvall, Claes; Lagou, Vasiliki; Lahti, Jari; Lecoeur, Cecile; Liu, Yongmei; Martinez-Larrad, Maria Teresa; Montasser, May E; Navarro, Pau; Perry, John R B; Rasmussen-Torvik, Laura J; Salo, Perttu; Sattar, Naveed; Shungin, Dmitry; Strawbridge, Rona J; Tanaka, Toshiko; van Duijn, Cornelia M; An, Ping; de Andrade, Mariza; Andrews, Jeanette S; Aspelund, Thor; Atalay, Mustafa; Aulchenko, Yurii; Balkau, Beverley; Bandinelli, Stefania; Beckmann, Jacques S; Beilby, John P; Bellis, Claire; Bergman, Richard N; Blangero, John; Boban, Mladen; Boehnke, Michael; Boerwinkle, Eric; Bonnycastle, Lori L; Boomsma, Dorret I; Borecki, Ingrid B; Böttcher, Yvonne; Bouchard, Claude; Brunner, Eric; Budimir, Danijela; Campbell, Harry; Carlson, Olga; Chines, Peter S; Clarke, Robert; Collins, Francis S; Corbatón-Anchuelo, Arturo; Couper, David; de Faire, Ulf; Dedoussis, George V; Deloukas, Panos; Dimitriou, Maria; Egan, Josephine M; Eiriksdottir, Gudny; Erdos, Michael R; Eriksson, Johan G; Eury, Elodie; Ferrucci, Luigi; Ford, Ian; Forouhi, Nita G; Fox, Caroline S; Franzosi, Maria Grazia; Franks, Paul W; Frayling, Timothy M; Froguel, Philippe; Galan, Pilar; de Geus, Eco; Gigante, Bruna; Glazer, Nicole L; Goel, Anuj; Groop, Leif; Gudnason, Vilmundur; Hallmans, Göran; Hamsten, Anders; Hansson, Ola; Harris, Tamara B; Hayward, Caroline; Heath, Simon; Hercberg, Serge; Hicks, Andrew A; Hingorani, Aroon; Hofman, Albert; Hui, Jennie; Hung, Joseph; Jarvelin, Marjo-Riitta; Jhun, Min A; Johnson, Paul C D; Jukema, J Wouter; Jula, Antti; Kao, W H; Kaprio, Jaakko; Kardia, Sharon L R; Keinanen-Kiukaanniemi, Sirkka; Kivimaki, Mika; Kolcic, Ivana; Kovacs, Peter; Kumari, Meena; Kuusisto, Johanna; Kyvik, Kirsten Ohm; Laakso, Markku; Lakka, Timo; Lannfelt, Lars; Lathrop, G Mark; Launer, Lenore J; Leander, Karin; Li, Guo; Lind, Lars; Lindstrom, Jaana; Lobbens, Stéphane; Loos, Ruth J F; Luan, Jian'an; Lyssenko, Valeriya; Mägi, Reedik; Magnusson, Patrik K E; Marmot, Michael; Meneton, Pierre; Mohlke, Karen L; Mooser, Vincent; Morken, Mario A; Miljkovic, Iva; Narisu, Narisu; O'Connell, Jeff; Ong, Ken K; Oostra, Ben A; Palmer, Lyle J; Palotie, Aarno; Pankow, James S; Peden, John F; Pedersen, Nancy L; Pehlic, Marina; Peltonen, Leena; Penninx, Brenda; Pericic, Marijana; Perola, Markus; Perusse, Louis; Peyser, Patricia A; Polasek, Ozren; Pramstaller, Peter P; Province, Michael A; Räikkönen, Katri; Rauramaa, Rainer; Rehnberg, Emil; Rice, Ken; Rotter, Jerome I; Rudan, Igor; Ruokonen, Aimo; Saaristo, Timo; Sabater-Lleal, Maria; Salomaa, Veikko; Savage, David B; Saxena, Richa; Schwarz, Peter; Seedorf, Udo; Sennblad, Bengt; Serrano-Rios, Manuel; Shuldiner, Alan R; Sijbrands, Eric J G; Siscovick, David S; Smit, Johannes H; Small, Kerrin S; Smith, Nicholas L; Smith, Albert Vernon; Stančáková, Alena; Stirrups, Kathleen; Stumvoll, Michael; Sun, Yan V; Swift, Amy J; Tönjes, Anke; Tuomilehto, Jaakko; Trompet, Stella; Uitterlinden, Andre G; Uusitupa, Matti; Vikström, Max; Vitart, Veronique; Vohl, Marie-Claude; Voight, Benjamin F; Vollenweider, Peter; Waeber, Gerard; Waterworth, Dawn M; Watkins, Hugh; Wheeler, Eleanor; Widen, Elisabeth; Wild, Sarah H; Willems, Sara M; Willemsen, Gonneke; Wilson, James F; Witteman, Jacqueline C M; Wright, Alan F; Yaghootkar, Hanieh; Zelenika, Diana; Zemunik, Tatijana; Zgaga, Lina; Wareham, Nicholas J; McCarthy, Mark I; Barroso, Ines; Watanabe, Richard M; Florez, Jose C; Dupuis, Josée; Meigs, James B; Langenberg, Claudia

2012-05-13

Recent genome-wide association studies have described many loci implicated in type 2 diabetes (T2D) pathophysiology and β-cell dysfunction but have contributed little to the understanding of the genetic basis of insulin resistance. We hypothesized that genes implicated in insulin resistance pathways might be uncovered by accounting for differences in body mass index (BMI) and potential interactions between BMI and genetic variants. We applied a joint meta-analysis approach to test associations with fasting insulin and glucose on a genome-wide scale. We present six previously unknown loci associated with fasting insulin at P < 5 × 10(-8) in combined discovery and follow-up analyses of 52 studies comprising up to 96,496 non-diabetic individuals. Risk variants were associated with higher triglyceride and lower high-density lipoprotein (HDL) cholesterol levels, suggesting a role for these loci in insulin resistance pathways. The discovery of these loci will aid further characterization of the role of insulin resistance in T2D pathophysiology.

The Role of Ventromedial Prefrontal Cortex in Text Comprehension Inferences: Semantic Coherence or Socio-Emotional Perspective?

PubMed Central

Burin, Debora I.; Acion, Laura; Kurczek, Jake; Duff, Melissa C.; Tranel, Daniel; Jorge, Ricardo E.

2015-01-01

Two hypotheses about the role of the ventromedial prefrontal cortex (vmPFC) in narrative comprehension inferences, global semantic coherence versus socio-emotional perspective, were tested. Seven patients with vmPFC lesions and seven demographically matched healthy comparison participants read short narratives. Using the consistency paradigm, narratives required participants to make either an emotional or visuo-spatial inference, in which a target sentence provided consistent or inconsistent information with a previous emotional state of a character or a visuo-spatial location of an object. Healthy comparison participants made the inferences both for spatial and emotional stories, as shown by longer reading times for inconsistent critical sentences. For patients with vmPFC lesions, inconsistent sentences were read slower in the spatial stories, but not in the emotional ones. This pattern of results is compatible with the hypothesis that vmPFC contributes to narrative comprehension by supporting inferences about socio-emotional aspects of verbally described situations. PMID:24561428

Orbital frontal cortex updates state-induced value change for decision-making.

PubMed

Baltz, Emily T; Yalcinbas, Ege A; Renteria, Rafael; Gremel, Christina M

2018-06-13

Recent hypotheses have posited that orbital frontal cortex (OFC) is important for using inferred consequences to guide behavior. Less clear is OFC's contribution to goal-directed or model-based behavior, where the decision to act is controlled by previous experience with the consequence or outcome. Investigating OFC's role in learning about changed outcomes separate from decision-making is not trivial and often the two are confounded. Here we adapted an incentive learning task to mice, where we investigated processes controlling experience-based outcome updating independent from inferred action control. We found chemogenetic OFC attenuation did not alter the ability to perceive motivational state-induced changes in outcome value but did prevent the experience-based updating of this change. Optogenetic inhibition of OFC excitatory neuron activity selectively when experiencing an outcome change disrupted the ability to update, leaving mice unable to infer the appropriate behavior. Our findings support a role for OFC in learning that controls decision-making. © 2018, Baltz et al.

Significant roles played by IL-10 in Chlamydia infections.

PubMed

Hakimi, Hamid; Zare-Bidaki, Mohammad; Zainodini, Nahid; Assar, Shokrollah; Arababadi, Mohammad Kazemi

2014-06-01

Chlamydia species are obligate intracellular parasites which cause usually asymptomatic genital tract infections and also are associated with several complications. Previous studies demonstrated that immune responses to Chlamydia species are different and the diseases will be limited to some cases. Additionally, Chlamydia species are able to modulate immune responses via regulating expression of some immune system molecules including cytokines. IL-10, as the main anti-inflammatory cytokine, plays important roles in the induction of immune-tolerance against self-antigen and also immune-homeostasis after microbe elimination. Furthermore, it has been documented that ectopic expression of IL-10 is associated with several chronic infectious diseases. Therefore, it can be hypothesized that changes in the regulation of this cytokine can be associated with infection with several species of Chlamydia and their associated complications. This review collected the recent information regarding the association and relationship of IL-10 with Chlamydia infections. Another aim of this review article is to address recent data regarding the association of genetic variations (polymorphisms) of IL-10 and Chlamydia infections.

Stepping out of the caveman's shadow: nations' gender gap predicts degree of sex differentiation in mate preferences.

PubMed

Zentner, Marcel; Mitura, Klaudia

2012-10-01

An influential explanation for gender differences in mating strategies is that the sex-specific reproductive constraints faced by human ancestors shaped these differences. Other theorists have emphasized the role of societal factors, hypothesizing, for example, that gender differences in mate preferences should wane in gender-equal societies. However, findings have been ambiguous. Using recent data and a novel measure of gender equality, we revisited the role of gender parity in gender differentiation for mate preferences. In the first study, 3,177 participants from 10 nations with a gradually decreasing Global Gender Gap Index (GGI) provided online ratings of the desirability of mate attributes with reportedly evolutionary origins. In the second study, GGI scores were related to gender differences in mate preferences previously reported for 8,953 participants from 31 nations (Buss, 1989). Both studies show that gender differences in mate preferences with presumed evolutionary roots decline proportionally to increases in nations' gender parity.

The role of immigrants in the assembly of the South American rainforest tree flora.

PubMed Central

Pennington, R Toby; Dick, Christopher W

2004-01-01

The Amazon lowland rainforest flora is conventionally viewed as comprising lineages that evolved in biogeographic isolation after the split of west Gondwana (ca. 100 Myr ago). Recent molecular phylogenies, however, identify immigrant lineages that arrived in South America during its period of oceanic isolation (ca. 100-3 Myr ago). Long-distance sweepstakes dispersal across oceans played an important and possibly predominant role. Stepping-stone migration from Africa and North America through hypothesized Late Cretaceous and Tertiary island chains may have facilitated immigration. An analysis of inventory plot data suggests that immigrant lineages comprise ca. 20% of both the species and individuals of an Amazon tree community in Ecuador. This is more than an order of magnitude higher than previous estimates. We also present data on the community-level similarity between South American and palaeotropical rainforests, and suggest that most taxonomic similarity derives from trans-oceanic dispersal, rather than a shared Gondwanan history. PMID:15519976

Demographic history and gene flow during silkworm domestication

PubMed Central

2014-01-01

Background Gene flow plays an important role in domestication history of domesticated species. However, little is known about the demographic history of domesticated silkworm involving gene flow with its wild relative. Results In this study, four model-based evolutionary scenarios to describe the demographic history of B. mori were hypothesized. Using Approximate Bayesian Computation method and DNA sequence data from 29 nuclear loci, we found that the gene flow at bottleneck model is the most likely scenario for silkworm domestication. The starting time of silkworm domestication was estimated to be approximate 7,500 years ago; the time of domestication termination was 3,984 years ago. Using coalescent simulation analysis, we also found that bi-directional gene flow occurred during silkworm domestication. Conclusions Estimates of silkworm domestication time are nearly consistent with the archeological evidence and our previous results. Importantly, we found that the bi-directional gene flow might occur during silkworm domestication. Our findings add a dimension to highlight the important role of gene flow in domestication of crops and animals. PMID:25123546

A Genome-Wide Association Study of the Human Metabolome in a Community-Based Cohort

PubMed Central

Rhee, Eugene P.; Ho, Jennifer E.; Chen, Ming-Huei; Shen, Dongxiao; Cheng, Susan; Larson, Martin G.; Ghorbani, Anahita; Shi, Xu; Helenius, Iiro T.; O’Donnell, Christopher J.; Souza, Amanda L.; Deik, Amy; Pierce, Kerry A.; Bullock, Kevin; Walford, Geoffrey A.; Vasan, Ramachandran S.; Florez, Jose C.; Clish, Clary; Yeh, J.-R. Joanna; Wang, Thomas J.; Gerszten, Robert E.

2014-01-01

SUMMARY Because metabolites are hypothesized to play key roles as markers and effectors of cardio-metabolic diseases, recent studies have sought to annotate the genetic determinants of circulating metabolite levels. We report a genome-wide association study (GWAS) of 217 plasma metabolites, including >100 not measured in prior GWAS, in 2,076 participants of the Framingham Heart Study. For the majority of analytes, we find that estimated heritability explains >20% of inter-individual variation, and that variation attributable to heritable factors is greater than that attributable to clinical factors. Further, we identify 31 genetic loci associated with plasma metabolites, including 23 that have not previously been reported. Importantly, we include GWAS results for all surveyed metabolites, and demonstrate how this information highlights a role for AGXT2 in cholesterol ester and triacylglycerol metabolism. Thus, our study outlines the relative contributions of inherited and clinical factors on the plasma metabolome and provides a resource for metabolism research. PMID:23823483

Role of GALNT12 in the genetic predisposition to attenuated adenomatous polyposis syndrome

PubMed Central

Lorca, Víctor; Rueda, Daniel; Martín-Morales, Lorena; Poves, Carmen; Fernández-Aceñero, María Jesús; Ruiz-Ponte, Clara; Llovet, Patricia; Marrupe, David; García-Barberán, Vanesa; García-Paredes, Beatriz; Pérez-Segura, Pedro; de la Hoya, Miguel; Díaz-Rubio, Eduardo; Caldés, Trinidad

2017-01-01

The involvement of GALNT12 in colorectal carcinogenesis has been demonstrated but it is not clear to what extent it is implicated in familial CRC susceptibility. Partially inactivating variant, NM_024642.4:c.907G>A, p.(D303N), has been previously detected in familial CRC and proposed as the causative risk allele. Since phenotypes of the described carrier families showed not only CRC but also a polyp history, we hypothesized that GALNT12 could be involved in adenoma predisposition and consequently, in hereditary polyposis CRC syndromes. For that purpose, we have screened the GALNT12 gene in germline DNA from 183 unrelated attenuated polyposis patients. c.907G>A, p.(D303N) was detected in 4 cases (MAF = 1.1%) and no other candidate variants were found. After segregation studies, LOH analyses, glycosylation pattern tests and case-control studies, our results did not support the role of c.907G>A, p.(D303N) as a high-penetrance risk allele for polyposis CRC. PMID:29095867

Self-Compassion and Responses to Trauma: The Role of Emotion Regulation.

PubMed

Scoglio, Arielle A J; Rudat, Deirdre A; Garvert, Donn; Jarmolowski, Maggie; Jackson, Christie; Herman, Judith L

2018-07-01

Emerging literature suggests that self-compassion may be an important concept for understanding recovery from the impact of trauma and posttraumatic stress disorder (PTSD). The present study explored the interconnection among self-compassion, resilience, emotion dysregulation, and PTSD symptom severity in a sample of treatment-seeking women with PTSD. We predicted that self-compassion would be negatively related to PTSD symptom severity and to emotion dysregulation, and positively related to resilience. The results supported our main hypotheses. In addition, emotion dysregulation mediated the relationship between PTSD symptom severity and self-compassion and affected the relationship between self-compassion and resilience. These findings corroborate previous research that points to the important role of self-compassion in mental health and in the aftermath of stressful life events. The present study expands this research by demonstrating that PTSD symptom severity is negatively related to self-compassion in a clinical population of women with experiences of severe and repeated interpersonal trauma.

Attachment as an organizer of behavior: implications for substance abuse problems and willingness to seek treatment

PubMed Central

Caspers, Kristin M; Yucuis, Rebecca; Troutman, Beth; Spinks, Ruth

2006-01-01

Background Attachment theory allows specific predictions about the role of attachment representations in organizing behavior. Insecure attachment is hypothesized to predict maladaptive emotional regulation whereas secure attachment is hypothesized to predict adaptive emotional regulation. In this paper, we test specific hypotheses about the role of attachment representations in substance abuse/dependence and treatment participation. Based on theory, we expect divergence between levels of maladaptive functioning and adaptive methods of regulating negative emotions. Methods Participants for this study consist of a sample of adoptees participating in an ongoing longitudinal adoption study (n = 208). The Semi-Structured Assessment of the Genetics of Alcohol-II [41] was used to determine lifetime substance abuse/dependence and treatment participation. Attachment representations were derived by the Adult Attachment Interview [AAI; [16

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).

Congruent biogeographical disjunctions at a continent-wide scale: Quantifying and clarifying the role of biogeographic barriers in the Australian tropics

PubMed Central

Crisp, Michael D.; Cook, Dianne H.; Cook, Lyn G.

2017-01-01

Aim To test whether novel and previously hypothesized biogeogaphic barriers in the Australian Tropics represent significant disjunction points or hard barriers, or both, to the distribution of plants. Location Australian tropics: Australian Monsoon Tropics and Australian Wet Tropics. Methods The presence or absence of 6,861 plant species was scored across 13 putative biogeographic barriers in the Australian Tropics, including two that have not previously been recognised. Randomizations of these data were used to test whether more species showed disjunctions (gaps in distribution) or likely barriers (range limits) at these points than expected by chance. Results Two novel disjunctions in the Australian Tropics flora are identified in addition to eleven putative barriers previously recognized for animals. Of these, eleven disjunction points (all within the Australian Monsoon Tropics) were found to correspond to range-ending barriers to a significant number of species, while neither of the two disjunctions found within the Australian Wet Tropics limited a significant number of species’ ranges. Main conclusions Biogeographic barriers present significant distributional limits to native plant species in the Australian Monsoon Tropics but not in the Australian Wet Tropics. PMID:28376094

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

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.

Molecular engineering and measurements to test hypothesized mechanisms in single molecule conductance switching.

PubMed

Moore, Amanda M; Dameron, Arrelaine A; Mantooth, Brent A; Smith, Rachel K; Fuchs, Daniel J; Ciszek, Jacob W; Maya, Francisco; Yao, Yuxing; Tour, James M; Weiss, Paul S

2006-02-15

Six customized phenylene-ethynylene-based oligomers have been studied for their electronic properties using scanning tunneling microscopy to test hypothesized mechanisms of stochastic conductance switching. Previously suggested mechanisms include functional group reduction, functional group rotation, backbone ring rotation, neighboring molecule interactions, bond fluctuations, and hybridization changes. Here, we test these hypotheses experimentally by varying the molecular designs of the switches; the ability of the molecules to switch via each hypothetical mechanism is selectively engineered into or out of each molecule. We conclude that hybridization changes at the molecule-surface interface are responsible for the switching we observe.

Bayes Factor Approaches for Testing Interval Null Hypotheses

ERIC Educational Resources Information Center

Morey, Richard D.; Rouder, Jeffrey N.

2011-01-01

Psychological theories are statements of constraint. The role of hypothesis testing in psychology is to test whether specific theoretical constraints hold in data. Bayesian statistics is well suited to the task of finding supporting evidence for constraint, because it allows for comparing evidence for 2 hypotheses against each another. One issue…

The Role of Feedback on Studying, Achievement and Calibration.

ERIC Educational Resources Information Center

Chu, Stephanie T. L.; Jamieson-Noel, Dianne L.; Winne, Philip H.

One set of hypotheses examined in this study was that various types of feedback (outcome, process, and corrective) supply different information about performance and have different effects on studying processes and on achievement. Another set of hypotheses concerned students' calibration, their accuracy in predicting and postdicting achievement…

EVENT-LEVEL ANALYSIS OF ANAL SEX ROLES AND SEX DRUG USE AMONG GAY AND BISEXUAL MEN IN VANCOUVER, BRITISH COLUMBIA, CANADA

PubMed Central

Rich, Ashleigh J; Lachowsky, Nathan J; Cui, Zishan; Sereda, Paul; Lal, Allan; Moore, David M; Hogg, Robert S; Roth, Eric A

2015-01-01

This study analyzed event-level partnership data from a computer-assisted survey of 719 gay and bisexual men (GBM) enrolled in the Momentum Health Study to delineate potential linkages between anal sex roles and so-called “sex drugs”, i.e. erectile dysfunction drugs (EDD), poppers and crystal methamphetamine. Univariable and multivariable analyses using generalized linear mixed models with logit link function with sexual encounters (n=2,514) as the unit of analysis tested four hypotheses: 1) EDD are significantly associated with insertive anal sex roles, 2) poppers are significantly associated with receptive anal sex, 3) both poppers and EDD are significantly associated with anal sexual versatility and, 4) crystal methamphetamine is significantly associated with all anal sex roles. Data for survey respondents and their sexual partners allowed testing these hypotheses for both anal sex partners in the same encounter. Multivariable results supported the first three hypotheses. Crystal methamphetamine was significantly associated with all anal sex roles in the univariable models, but not significant in any multivariable ones. Other multivariable significant variables included attending group sex events, venue where first met, and self-described sexual orientation. Results indicate that GBM sex-drug use behavior features rational decision-making strategies linked to anal sex roles. They also suggest that more research on anal sex roles, particularly versatility, is needed, and that sexual behavior research can benefit from partnership analysis. PMID:26525571

Event-Level Analysis of Anal Sex Roles and Sex Drug Use Among Gay and Bisexual Men in Vancouver, British Columbia, Canada.

PubMed

Rich, Ashleigh J; Lachowsky, Nathan J; Cui, Zishan; Sereda, Paul; Lal, Allan; Moore, David M; Hogg, Robert S; Roth, Eric A

2016-08-01

This study analyzed event-level partnership data from a computer-assisted survey of 719 gay and bisexual men (GBM) enrolled in the Momentum Health Study to delineate potential linkages between anal sex roles and the so-called "sex drugs," i.e., erectile dysfunction drugs (EDD), poppers, and crystal methamphetamine. Univariable and multivariable analyses using generalized linear mixed models with logit link function with sexual encounters (n = 2514) as the unit of analysis tested four hypotheses: (1) EDD are significantly associated with insertive anal sex roles, (2) poppers are significantly associated with receptive anal sex, (3) both poppers and EDD are significantly associated with anal sexual versatility, and (4) crystal methamphetamine is significantly associated with all anal sex roles. Data for survey respondents and their sexual partners allowed testing these hypotheses for both anal sex partners in the same encounter. Multivariable results supported the first three hypotheses. Crystal methamphetamine was significantly associated with all anal sex roles in the univariable models, but not significant in any multivariable ones. Other multivariable significant variables included attending group sex events, venue where first met, and self-described sexual orientation. Results indicate that GBM sex-drug use behavior features rational decision-making strategies linked to anal sex roles. They also suggest that more research on anal sex roles, particularly versatility, is needed, and that sexual behavior research can benefit from partnership analysis.

The role of probability arguments in the history of science.

PubMed

Weinert, Friedel

2010-03-01

The paper examines Wesley Salmon's claim that the primary role of plausibility arguments in the history of science is to impose constraints on the prior probability of hypotheses (in the language of Bayesian confirmation theory). A detailed look at Copernicanism and Darwinism and, more briefly, Rutherford's discovery of the atomic nucleus reveals a further and arguably more important role of plausibility arguments. It resides in the consideration of likelihoods, which state how likely a given hypothesis makes a given piece of evidence. In each case the likelihoods raise the probability of one of the competing hypotheses and diminish the credibility of its rival, and this may happen either on the basis of 'old' or 'new' evidence.

Building the infrastructure: the effects of role identification behaviors on team cognition development and performance.

PubMed

Pearsall, Matthew J; Ellis, Aleksander P J; Bell, Bradford S

2010-01-01

The primary purpose of this study was to extend theory and research regarding the emergence of mental models and transactive memory in teams. Utilizing Kozlowski, Gully, Nason, and Smith's (1999) model of team compilation, we examined the effect of role identification behaviors and posited that such behaviors represent the initial building blocks of team cognition during the role compilation phase of team development. We then hypothesized that team mental models and transactive memory would convey the effects of these behaviors onto team performance in the team compilation phase of development. Results from 60 teams working on a command-and-control simulation supported our hypotheses. Copyright 2009 APA, all rights reserved.

Neighborhoods as a Power Factor.

ERIC Educational Resources Information Center

Woody, Bette; And Others

1980-01-01

Examines Washington, DC, Advisory Neighborhood Commissions (ANC) as an illustration of neighborhood involvement in city revitalization and maintenance. Considers (1) hypotheses about neighborhood roles and participation in public issue raising; (2) ANC structure, participation, and decision roles; and (3) likely roles neighborhood governments can…

Hypothesis testing on the fractal structure of behavioral sequences: the Bayesian assessment of scaling methodology.

PubMed

Moscoso del Prado Martín, Fermín

2013-12-01

I introduce the Bayesian assessment of scaling (BAS), a simple but powerful Bayesian hypothesis contrast methodology that can be used to test hypotheses on the scaling regime exhibited by a sequence of behavioral data. Rather than comparing parametric models, as typically done in previous approaches, the BAS offers a direct, nonparametric way to test whether a time series exhibits fractal scaling. The BAS provides a simpler and faster test than do previous methods, and the code for making the required computations is provided. The method also enables testing of finely specified hypotheses on the scaling indices, something that was not possible with the previously available methods. I then present 4 simulation studies showing that the BAS methodology outperforms the other methods used in the psychological literature. I conclude with a discussion of methodological issues on fractal analyses in experimental psychology. PsycINFO Database Record (c) 2014 APA, all rights reserved.

For things needing your attention: the role of neocortical gamma in sensory perception.

PubMed

Pritchett, Dominique L; Siegle, Joshua H; Deister, Christopher A; Moore, Christopher I

2015-04-01

Two general classes of hypotheses for the role for gamma oscillations in sensation are those that predict gamma facilitates signal amplification through local synchronization of a distinct ensemble, and those that predict gamma modulates fine temporal relationships between neurons to represent information. Correlative evidence has been offered for and against these hypotheses. A recent study in which gamma was optogenetically entrained by driving fast-spiking interneurons showed enhanced sensory detection of harder-to-perceive stimuli, those that benefit most from attention, in agreement with the amplification hypotheses. These findings are supported by similar studies employing less specific optogenetic patterns or single neuron stimulation, but contrast with findings based on direct optogenetic stimulation of pyramidal neurons. Key next steps for this topic are described. Copyright © 2015 Elsevier Ltd. All rights reserved.

Upregulation of proinflammatory genes in skin lesions may be the cause of keloid formation (Review)

PubMed Central

DONG, XIANGLIN; MAO, SHAOLIN; WEN, HAO

2013-01-01

It was previously demonstrated that the main cause behind keloid formation may be keloid fibroblast abnormalities, which are closely associated with the microenvironment of the keloid lesion. The post-traumatic and chronic inflammation of the keloid lesion area suggest that inflammatory mediators play an important role in the keloid microenvironment and are crucial for keloid fibroblast abnormalities. In this study, we hypothesized that the mechanism underlying keloid formation may involve the continuous upregulation of proinflammatory gene expression in keloid lesions. This hypothesis may explain the inflammatory response, invasive growth and recurrence following resection of keloids, as well as the selective localization of keloids in specific parts of a patient’s body and the differences in localization among different patients. PMID:24649037

Nature gives us strength: exposure to nature counteracts ego-depletion.

PubMed

Chow, Jason T; Lau, Shun

2015-01-01

Previous research rarely investigated the role of physical environment in counteracting ego-depletion. In the present research, we hypothesized that exposure to natural environment counteracts ego-depletion. Three experiments were conducted to test this hypothesis. In Experiment 1, initially depleted participants who viewed pictures of nature scenes showed greater persistence on a subsequent anagram task than those who were given a rest period. Experiment 2 expanded upon this finding by showing that natural environment enhanced logical reasoning performance after ego-depleting task. Experiment 3 adopted a two- (depletion vs. no-depletion) -by-two (nature exposure vs. urban exposure) factorial design. We found that nature exposure moderated the effect of depletion on anagram task performance. Taken together, the present studies offer a viable and novel strategy to mitigate the negative impacts of ego-depletion.

Catalytic autoantibodies against myelin basic protein (MBP) isolated from serum of autistic children impair in vitro models of synaptic plasticity in rat hippocampus.

PubMed

Gonzalez-Gronow, Mario; Cuchacovich, Miguel; Francos, Rina; Cuchacovich, Stephanie; Blanco, Angel; Sandoval, Rodrigo; Gomez, Cristian Farias; Valenzuela, Javier A; Ray, Rupa; Pizzo, Salvatore V

2015-10-15

Autoantibodies from autistic spectrum disorder (ASD) patients react with multiple proteins expressed in the brain. One such autoantibody targets myelin basic protein (MBP). ASD patients have autoantibodies to MBP of both the IgG and IgA classes in high titers, but no autoantibodies of the IgM class. IgA autoantibodies act as serine proteinases and degrade MBP in vitro. They also induce a decrease in long-term potentiation in the hippocampi of rats either perfused with or previously inoculated with this IgA. Because this class of autoantibody causes myelin sheath destruction in multiple sclerosis (MS), we hypothesized a similar pathological role for them in ASD. Copyright © 2015 Elsevier B.V. All rights reserved.

A case of mental nerve paresthesia due to dynamic compression of alveolar inferior nerve along an elongated styloid process.

PubMed

Gooris, Peter J J; Zijlmans, Jan C M; Bergsma, J Eelco; Mensink, Gertjan

2014-07-01

Spontaneous paresthesia of the mental nerve is considered an ominous clinical sign. Mental nerve paresthesia has also been referred to as numb chin syndrome. Several potentially different factors have been investigated for their role in interfering with the inferior alveolar nerve (IAN) and causing mental nerve neuropathy. In the present case, the patient had an elongated calcified styloid process that we hypothesized had caused IAN irritation during mandibular movement. This eventually resulted in progressive loss of sensation in the mental nerve region. To our knowledge, this dynamic irritation, with complete recovery after resection of the styloid process, has not been previously reported. Copyright © 2014 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

Role of prefrontal cortex and the midbrain dopamine system in working memory updating

PubMed Central

D’Ardenne, Kimberlee; Eshel, Neir; Luka, Joseph; Lenartowicz, Agatha; Nystrom, Leigh E.; Cohen, Jonathan D.

2012-01-01

Humans are adept at switching between goal-directed behaviors quickly and effectively. The prefrontal cortex (PFC) is thought to play a critical role by encoding, updating, and maintaining internal representations of task context in working memory. It has also been hypothesized that the encoding of context representations in PFC is regulated by phasic dopamine gating signals. Here we use multimodal methods to test these hypotheses. First we used functional MRI (fMRI) to identify regions of PFC associated with the representation of context in a working memory task. Next we used single-pulse transcranial magnetic stimulation (TMS), guided spatially by our fMRI findings and temporally by previous event-related EEG recordings, to disrupt context encoding while participants performed the same working memory task. We found that TMS pulses to the right dorsolateral PFC (DLPFC) immediately after context presentation, and well in advance of the response, adversely impacted context-dependent relative to context-independent responses. This finding causally implicates right DLPFC function in context encoding. Finally, using the same paradigm, we conducted high-resolution fMRI measurements in brainstem dopaminergic nuclei (ventral tegmental area and substantia nigra) and found phasic responses after presentation of context stimuli relative to other stimuli, consistent with the timing of a gating signal that regulates the encoding of representations in PFC. Furthermore, these responses were positively correlated with behavior, as well as with responses in the same region of right DLPFC targeted in the TMS experiment, lending support to the hypothesis that dopamine phasic signals regulate encoding, and thereby the updating, of context representations in PFC. PMID:23086162

Augmented sympathetic vasoconstriction in exercising forearms of postmenopausal women is reversed by oestrogen therapy

PubMed Central

Fadel, Paul J; Wang, Zhongyun; Watanabe, Hitoshi; Arbique, Debbie; Vongpatanasin, Wanpen; Thomas, Gail D

2004-01-01

Sympathetic vasoconstriction is normally attenuated in exercising muscles of young men and women. Recent evidence indicates that such modulation, termed functional sympatholysis, may be impaired in older men. Whether a similar impairment occurs in older women, and what role oestrogen deficiency might play in this impairment, are not known. Based on the strong positive correlation between circulating oestrogen levels and functional sympatholysis previously reported in female rats, we hypothesized that sympatholysis would be impaired in oestrogen-deficient postmenopausal women, and that this impairment would be reversed by oestrogen replacement. To test these hypotheses, we measured vasoconstrictor responses in the forearms of pre- and postmenopausal women using near infrared spectroscopy to detect decreases in muscle oxygenation in response to reflex activation of sympathetic nerves evoked by lower body negative pressure (LBNP). In eight premenopausal women, LBNP decreased muscle oxygenation by 20 ± 1% in resting forearm, but only by 3 ± 2% in exercising forearm (P < 0.05). In contrast, in eight postmenopausal women, LBNP decreased muscle oxygenation by 15 ± 3% in resting forearm, and by 12 ± 4% in exercising forearm (P > 0.05). After 1 month of transdermal oestradiol replacement in these women, the normal effect of exercise to blunt sympathetic vasoconstriction was restored (rest, −19 ± 3%; exercise, −2 ± 3%; P < 0.05). These data indicate that functional sympatholysis is impaired in oestrogen-deficient postmenopausal women. The effect of short-term unopposed oestrogen replacement to correct this impairment implicates a role for oestrogen in the sympathetic neural control of muscle haemodynamics during exercise. PMID:15498809

Multiple brain networks for visual self-recognition with different sensitivity for motion and body part.

PubMed

Sugiura, Motoaki; Sassa, Yuko; Jeong, Hyeonjeong; Miura, Naoki; Akitsuki, Yuko; Horie, Kaoru; Sato, Shigeru; Kawashima, Ryuta

2006-10-01

Multiple brain networks may support visual self-recognition. It has been hypothesized that the left ventral occipito-temporal cortex processes one's own face as a symbol, and the right parieto-frontal network processes self-image in association with motion-action contingency. Using functional magnetic resonance imaging, we first tested these hypotheses based on the prediction that these networks preferentially respond to a static self-face and to moving one's whole body, respectively. Brain activation specifically related to self-image during familiarity judgment was compared across four stimulus conditions comprising a two factorial design: factor Motion contrasted picture (Picture) and movie (Movie), and factor Body part a face (Face) and whole body (Body). Second, we attempted to segregate self-specific networks using a principal component analysis (PCA), assuming an independent pattern of inter-subject variability in activation over the four stimulus conditions in each network. The bilateral ventral occipito-temporal and the right parietal and frontal cortices exhibited self-specific activation. The left ventral occipito-temporal cortex exhibited greater self-specific activation for Face than for Body, in Picture, consistent with the prediction for this region. The activation profiles of the right parietal and frontal cortices did not show preference for Movie Body predicted by the assumed roles of these regions. The PCA extracted two cortical networks, one with its peaks in the right posterior, and another in frontal cortices; their possible roles in visuo-spatial and conceptual self-representations, respectively, were suggested by previous findings. The results thus supported and provided evidence of multiple brain networks for visual self-recognition.

Deciphering the role of a coleopteran steering muscle via free flight stimulation.

PubMed

Sato, Hirotaka; Vo Doan, Tat Thang; Kolev, Svetoslav; Huynh, Ngoc Anh; Zhang, Chao; Massey, Travis L; van Kleef, Joshua; Ikeda, Kazuo; Abbeel, Pieter; Maharbiz, Michel M

2015-03-16

Testing hypotheses of neuromuscular function during locomotion ideally requires the ability to record cellular responses and to stimulate the cells being investigated to observe downstream behaviors [1]. The inability to stimulate in free flight has been a long-standing hurdle for insect flight studies. The miniaturization of computation and communication technologies has delivered ultra-small, radio-enabled neuromuscular recorders and stimulators for untethered insects [2-8]. Published stimulation targets include the areas in brain potentially responsible for pattern generation in locomotion [5], the nerve chord for abdominal flexion [9], antennal muscles [2, 10], and the flight muscles (or their excitatory junctions) [7, 11-13]. However, neither fine nor graded control of turning has been demonstrated in free flight, and responses to the stimulation vary widely [2, 5, 7, 9]. Technological limitations have precluded hypotheses of function validation requiring exogenous stimulation during flight. We investigated the role of a muscle involved in wing articulation during flight in a coleopteran. We set out to identify muscles whose stimulation produced a graded turning in free flight, a feat that would enable fine steering control not previously demonstrated. We anticipated that gradation might arise either as a function of the phase of muscle firing relative to the wing stroke (as in the classic fly b1 muscle [14, 15] or the dorsal longitudinal and ventral muscles of moth [16]), or due to regulated tonic control, in which phase-independent summation of twitch responses produces varying amounts of force delivered to the wing linkages [15, 17, 18]. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

Rbpj-κ mediated Notch signaling plays a critical role in development of hypothalamic Kisspeptin neurons

PubMed Central

Biehl, Matthew J; Raetzman, Lori T

2015-01-01

The mammalian arcuate nucleus (ARC) houses neurons critical for energy homeostasis and sexual maturation. Proopiomelanocortin (POMC) and Neuropeptide Y (NPY) neurons function to balance energy intake and Kisspeptin neurons are critical for the onset of puberty and reproductive function. While the physiological roles of these neurons have been well established, their development remains unclear. We have previously shown that Notch signaling plays an important role in cell fate within the ARC of mice. Active Notch signaling prevented neural progenitors from differentiating into feeding circuit neurons, whereas conditional loss of Notch signaling lead to a premature differentiation of these neurons. Presently, we hypothesized that Kisspeptin neurons would similarly be affected by Notch manipulation. To address this, we utilized mice with a conditional deletion of the Notch signaling co-factor Rbpj-κ (Rbpj cKO), or mice persistently expressing the Notch1 intracellular domain (NICD tg) within Nkx2.1 expressing cells of the developing hypothalamus. Interestingly, we found that in both models, a lack of Kisspeptin neurons are observed. This suggests that Notch signaling must be properly titrated for formation of Kisspeptin neurons. These results led us to hypothesize that Kisspeptin neurons of the ARC may arise from a different lineage of intermediate progenitors than NPY neurons and that Notch was responsible for the fate choice between these neurons. To determine if Kisspeptin neurons of the ARC differentiate similarly through a Pomc intermediate, we utilized a genetic model expressing the tdTomato fluorescent protein in all cells that have ever expressed Pomc. We observed some Kisspeptin expressing neurons labeled with the Pomc reporter similar to NPY neurons, suggesting that these distinct neurons can arise from a common progenitor. Finally, we hypothesized that temporal differences leading to premature depletion of progenitors in cKO mice lead to our observed phenotype. Using a BrdU birthdating paradigm, we determined the percentage of NPY and Kisspeptin neurons born on embryonic days 11.5, 12.5, and 13.5. We found no difference in the timing of differentiation of either neuronal subtype, with a majority occurring at e11.5. Taken together, our findings suggest that active Notch signaling is an important molecular switch involved in instructing subpopulations of progenitor cells to differentiate into Kisspeptin neurons. PMID:26318021

The impact of role stress on workers' behaviour through job satisfaction and organizational commitment.

PubMed

Antón, Concha

2009-06-01

Dysfunctions in role performance have been associated with a large number of consequences, almost always negative, which affect the well-being of workers and the functioning of organizations. An individual's experience of receiving incompatible or conflicting requests (role conflict) and/or the lack of enough information to carry out his/her job (role ambiguity) are causes of role stress. According to previous theory, role ambiguity and conflict decrease workers' performance and are positively related to the probability of workers leaving the organization. Job satisfaction refers to a positive evaluation of a job, while organizational commitment refers to an employee's attachment to the organization. The affective dimensions of organizational commitment and job satisfaction are considered to be important predictors of turnover intention, absenteeism, and job performance. In the literature, role conflict and ambiguity have been proposed as determining factors of workers' job satisfaction and their commitment towards the organization. The role of job satisfaction and organizational commitment were analysed as variables that should mediate between role ambiguity and conflict and employees' behaviour. The hypotheses were confirmed by means of path analysis carried out with data obtained from a sample of Spanish blue-collar workers employed by a bus company and a water supply company. Role stressors were negatively related to affective commitment mediated through job satisfaction. Affective commitment to the organization exerted a positive influence on performance and reduces the withdrawal behaviour analysed— intention to leave and absenteeism—although the strongest predictor of intention to leave was, in this study, job satisfaction.

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,…

Impact of Scaffolding and Question Structure on the Gender Gap

ERIC Educational Resources Information Center

Dawkins, Hillary; Hedgeland, Holly; Jordan, Sally

2017-01-01

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…

Interactions between Cultural and Economic Determinants of Divorce in the Netherlands

ERIC Educational Resources Information Center

Kalmijn, Matthijs; De Graaf, Paul M.; Poortman, Annerigt

2004-01-01

This study examines the relationship between gendered family roles and divorce in The Netherlands. Cultural and economic aspects of this relationship are distinguished. Economic hypotheses argue that the likelihood of divorce is increased if women work for pay and have attractive labor market resources. Cultural hypotheses argue that divorce…

The Origins of Children's Career Aspirations: IV. Testing Hypotheses from Four Theories.

ERIC Educational Resources Information Center

Trice, Ashton D.; And Others

1995-01-01

A study of elementary students (n=949) revealed some support for each of the hypotheses of Ginzberg, Roe, and Havinghurst. Results indicate that interests play the major role in both the selection and rejection of careers throughout childhood, that family configuration influenced occupational choice/no choice, and that identification with a…

Moderators of the relationship between masculinity and sexual prejudice in men: friendship, gender self-esteem, same-sex attraction, and religious fundamentalism.

PubMed

Mellinger, Christopher; Levant, Ronald F

2014-04-01

Masculinity has been found to predict the sexual prejudice of heterosexual men against gay men. The present study investigated the role of four variables as moderators of the relationships between two masculinity constructs (endorsement of traditional masculinity ideology and gender role conflict) and sexual prejudice in men. The hypothesized moderators were: direct and indirect friendships with gay men, gender self-esteem, acknowledged same-sex attraction, and religious fundamentalism. A total of 383 men completed 8 scales plus a demographic questionnaire. Direct friendship strengthened the positive relationship between masculinity ideology and sexual prejudice, contrary to hypothesis. This finding could mean that high masculinity ideology scores reduced the likelihood that a man with many gay friends would let go of his prejudice. Direct friendship did not moderate the relationship between gender role conflict and sexual prejudice nor did indirect friendship moderate either relationship; however, both forms of friendship predicted prejudice, as hypothesized. Gender self-esteem strengthened the positive relationships between both masculinity variables and sexual prejudice as hypothesized. Same-sex attraction weakened the relationship between gender role conflict and sexual prejudice as hypothesized, but contrary to hypothesis did not moderate the relationship between masculinity ideology and sexual prejudice. Religious fundamentalism predicted prejudice, but showed no significant moderation. The results were discussed in terms of limitations and suggestions for future research and application. In conclusion, this line of investigation appears promising and should be continued and the present findings can be utilized in anti-prejudice social marketing campaigns and in counseling.

Interaction and Role Strain: One-Parent Versus Two-Parent Situations.

ERIC Educational Resources Information Center

Wylie, Mary Lou

The potential for role strain is much greater in single-parent families where one person functions as both caretaker and provider than in the two-parent household where these roles can be shared. Role strain affects the quality of relationshps and the interactions between parent and child(ren). It was hypothesized that the role strain felt by…

Gonadal steroids and bone metabolism in men.

PubMed

Leder, Benjamin

2007-06-01

Over the past decade, our increasing awareness of the clinical importance of osteoporosis in men has stimulated intense interest in trying to better understand male skeletal physiology and pathophysiology. The present review focuses on a major focus of research in this area, namely the attempt to define the influence and therapeutic potential of gonadal steroids in male bone metabolism. Building on previous work defining the relative roles of androgens and estrogens in the developing male skeleton and in maintaining normal bone turnover, recent studies have begun to define these issues from epidemiologic, physiologic and therapeutic perspectives. With access to data from large prospectively defined populations of men, investigators are confirming and challenging existing hypotheses and forwarding new concepts. Clinical trials have expanded beyond standard androgen replacement studies to explore more complex hormonal interventions. Physiologic investigation has continued to probe the mechanisms underlying the differential and independent roles of androgens and estrogens in male bone metabolism. Recent work has added significantly to our understanding of the role of gonadal steroids in male skeletal physiology. Nonetheless, further research is necessary to build on these initial human studies and to capitalize on rapidly emerging advances in our understanding of the basic biology of bone metabolism.

Oxidation-specific epitopes are dominant targets of innate natural antibodies in mice and humans

PubMed Central

Chou, Meng-Yun; Fogelstrand, Linda; Hartvigsen, Karsten; Hansen, Lotte F.; Woelkers, Douglas; Shaw, Peter X.; Choi, Jeomil; Perkmann, Thomas; Bäckhed, Fredrik; Miller, Yury I.; Hörkkö, Sohvi; Corr, Maripat; Witztum, Joseph L.; Binder, Christoph J.

2009-01-01

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of oxidized lipoproteins and apoptotic cells. Adaptive immune responses to various oxidation-specific epitopes play an important role in atherogenesis. However, accumulating evidence suggests that these epitopes are also recognized by innate receptors, such as scavenger receptors on macrophages, and plasma proteins, such as C-reactive protein (CRP). Here, we provide multiple lines of evidence that oxidation-specific epitopes constitute a dominant, previously unrecognized target of natural Abs (NAbs) in both mice and humans. Using reconstituted mice expressing solely IgM NAbs, we have shown that approximately 30% of all NAbs bound to model oxidation-specific epitopes, as well as to atherosclerotic lesions and apoptotic cells. Because oxidative processes are ubiquitous, we hypothesized that these epitopes exert selective pressure to expand NAbs, which in turn play an important role in mediating homeostatic functions consequent to inflammation and cell death, as demonstrated by their ability to facilitate apoptotic cell clearance. These findings provide novel insights into the functions of NAbs in mediating host homeostasis and into their roles in health and diseases, such as chronic inflammatory diseases and atherosclerosis. PMID:19363291

The prospective relationship between role stressors and new cases of self-reported workplace bullying.

PubMed

Reknes, Iselin; Einarsen, Ståle; Knardahl, Stein; Lau, Bjørn

2014-02-01

In line with the "Work environment hypothesis," role stressors have been proposed as important antecedents of bullying in the workplace. Only a few longitudinal studies on the relationship between role stressors and bullying exist, however, and earlier studies have largely been cross-sectional. The aim of the present prospective study was to determine whether role stressors at baseline predict new cases of workplace bullying at follow-up. A total of 2,835 Norwegian employees participated at both baseline and follow-up, with an interval of two years between the measurements. The study supports the hypotheses that role ambiguity and role conflict, independently, contribute to subsequent new reports of workplace bullying. However, there was a weak reverse effect: reporting being bullied at work at baseline predicted reporting increased levels of role ambiguity and role conflict at follow-up. Even though the results may indicate a circular relationship between the variables at hand, the weak reverse relationship seems to have little practical impact compared to the stronger relationship from role stressors to bullying. Hence, the results mainly support the hypotheses stating that role ambiguity and role conflict, independently, predict subsequent exposure to workplace bullying.

Learned predictiveness and outcome predictability effects are not simply two sides of the same coin.

PubMed

Thorwart, Anna; Livesey, Evan J; Wilhelm, Francisco; Liu, Wei; Lachnit, Harald

2017-10-01

The Learned Predictiveness effect refers to the observation that learning about the relationship between a cue and an outcome is influenced by the predictive relevance of the cue for other outcomes. Similarly, the Outcome Predictability effect refers to a recent observation that the previous predictability of an outcome affects learning about this outcome in new situations, too. We hypothesize that both effects may be two manifestations of the same phenomenon and stimuli that have been involved in highly predictive relationships may be learned about faster when they are involved in new relationships regardless of their functional role in predictive learning as cues and outcomes. Four experiments manipulated both the relationships and the function of the stimuli. While we were able to replicate the standard effects, they did not survive a transfer to situations where the functional role of the stimuli changed, that is the outcome of the first phase becomes a cue in the second learning phase or the cue of the first phase becomes the outcome of the second phase. Furthermore, unlike learned predictiveness, there was little indication that the distribution of overt attention in the second phase was influenced by previous predictability. The results suggest that these 2 very similar effects are not manifestations of a more general phenomenon but rather independent from each other. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The 22 March 2014 Oso landslide, Washington, USA

NASA Astrophysics Data System (ADS)

Wartman, Joseph; Montgomery, David R.; Anderson, Scott A.; Keaton, Jeffrey R.; Benoît, Jean; dela Chapelle, John; Gilbert, Robert

2016-01-01

The Oso, Washington, USA, landslide occurred on the morning of Saturday, 22 March 2014 and claimed the lives of 43 people. The landslide began within an 200-m-high hillslope comprised of unconsolidated glacial and previous landslide/colluvial deposits; it continued as a debris avalanche/debris flow that rapidly inundated a neighborhood of 35 single-family residences. An intense three-week rainfall that immediately preceded the event most likely played a role in triggering the landslide; and other factors that likely contributed to destabilization of the landslide mass include alteration of the local groundwater recharge and hydrogeological regime from previous landsliding, weakening and alteration of the landslide mass caused by previous landsliding, and changes in stress distribution resulting from removal and deposition of material from earlier landsliding. Field reconnaissance following the event revealed six distinctive zones and several subzones that are characterized on the basis of geomorphic expression, styles of deformation, geologic materials, and the types, size, and orientation of vegetation. Seismic recording of the landslide indicate that the event was marked by several vibration-generating episodes of mass movement. We hypothesize that the landslide occurred in two stages, with the first being a sequential remobilization of existing slide masses from the most recent (2006) landslide and from an ancient slide that triggered a devastating debris avalanche/debris flow. The second stage involved headward extension into previously unfailed material that occurred in response to unloading and redirection of stresses.

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.

Progressive Climate Change on Titan: Implications for Habitability

NASA Technical Reports Server (NTRS)

Moore, J. M.; A. D. Howard

2014-01-01

Titan's landscape is profoundly shaped by its atmosphere and comparable in magnitude perhaps with only the Earth and Mars amongst the worlds of the Solar System. Like the Earth, climate dictates the intensity and relative roles of fluvial and aeolian activity from place to place and over geologic time. Thus Titan's landscape is the record of climate change. We have investigated three broad classes of Titan climate evolution hypotheses (Steady State, Progressive, and Cyclic), regulated by the role, sources, and availability of methane. We favor the Progressive hypotheses, which we will outline here, then discuss their implication for habitability.

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.

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.

Push-you-pull-you: the boundaried self in close relationships.

PubMed

Rempel, John K; Burris, Christopher T

2006-02-01

Based on Amoebic Self Theory, the authors propose that the salience of different threats to the self affects the extent to which an intimate relationship partner is pushed away (excluded) or pulled closer (included). When social threat is salient among persons in relationships, it is hypothesized that partners will attempt to defuse the resulting sense of interpersonal vulnerability: offending partners may be pushed away, whereas offenders themselves may draw closer. When spatial-symbolic threat is salient and the relationship's capacity to function as an identity marker is jeopardized, it is hypothesized that the partner--regardless of his or her role--will be pulled closer to maintain the perception that the relationship is secure. Self-report responses to hypothetical scenarios and perceptions of behaviors during a role-play were generally consistent with these hypotheses, suggesting that both an intimate partner and the relationship with that partner can be incorporated into the self.

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

ERIC Educational Resources Information Center

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

2006-01-01

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…

Anxiety and Career Exploration: Gender Differences in the Role of Self-Construal

ERIC Educational Resources Information Center

Hardin, Erin E.; Varghese, Femina P.; Tran, Uyen V.; Carlson, Aaron Z.

2006-01-01

Given the social nature of many tasks involved in exploring and committing to a career, we hypothesized that social anxiety would correlate to exploration and commitment, even after controlling for general anxiety. We also hypothesized that self-construal and gender would interact with social anxiety in relation to exploration and commitment. In a…

Why Are Omics Technologies Important to Understanding the Role of Nutrition in Inflammatory Bowel Diseases?

PubMed Central

Ferguson, Lynnette R.; Barnett, Matthew P. G.

2016-01-01

For many years, there has been confusion about the role that nutrition plays in inflammatory bowel diseases (IBD). It is apparent that good dietary advice for one individual may prove inappropriate for another. As with many diseases, genome-wide association studies across large collaborative groups have been important in revealing the role of genetics in IBD, with more than 200 genes associated with susceptibility to the disease. These associations provide clues to explain the differences in nutrient requirements among individuals. In addition to genes directly involved in the control of inflammation, a number of the associated genes play roles in modulating the gut microbiota. Cell line models enable the generation of hypotheses as to how various bioactive dietary components might be especially beneficial for certain genetic groups. Animal models are necessary to mimic aspects of the complex aetiology of IBD, and provide an important link between tissue culture studies and human trials. Once we are sufficiently confident of our hypotheses, we can then take modified diets to an IBD population that is stratified according to genotype. Studies in IBD patients fed a Mediterranean-style diet have been important in validating our hypotheses and as a proof-of-principle for the application of these sensitive omics technologies to aiding in the control of IBD symptoms. PMID:27775675

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.

Rare variants in axonogenesis genes connect three families with sound-color synesthesia.

PubMed

Tilot, Amanda K; Kucera, Katerina S; Vino, Arianna; Asher, Julian E; Baron-Cohen, Simon; Fisher, Simon E

2018-03-20

Synesthesia is a rare nonpathological phenomenon where stimulation of one sense automatically provokes a secondary perception in another. Hypothesized to result from differences in cortical wiring during development, synesthetes show atypical structural and functional neural connectivity, but the underlying molecular mechanisms are unknown. The trait also appears to be more common among people with autism spectrum disorder and savant abilities. Previous linkage studies searching for shared loci of large effect size across multiple families have had limited success. To address the critical lack of candidate genes, we applied whole-exome sequencing to three families with sound-color (auditory-visual) synesthesia affecting multiple relatives across three or more generations. We identified rare genetic variants that fully cosegregate with synesthesia in each family, uncovering 37 genes of interest. Consistent with reports indicating genetic heterogeneity, no variants were shared across families. Gene ontology analyses highlighted six genes- COL4A1 , ITGA2 , MYO10 , ROBO3 , SLC9A6 , and SLIT2 -associated with axonogenesis and expressed during early childhood when synesthetic associations are formed. These results are consistent with neuroimaging-based hypotheses about the role of hyperconnectivity in the etiology of synesthesia and offer a potential entry point into the neurobiology that organizes our sensory experiences. Copyright © 2018 the Author(s). Published by PNAS.

Post-glacial recolonization of the Great Lakes region by the common gartersnake (Thamnophis sirtalis) inferred from mtDNA sequences.

PubMed

Placyk, John S; Burghardt, Gordon M; Small, Randall L; King, Richard B; Casper, Gary S; Robinson, Jace W

2007-05-01

Pleistocene events played an important role in the differentiation of North American vertebrate populations. Michigan, in particular, and the Great Lakes region, in general, were greatly influenced by the last glaciation. While several hypotheses regarding the recolonization of this region have been advanced, none have been strongly supported. We generated 148 complete ND2 mitochondrial DNA (mtDNA) sequences from common gartersnake (Thamnophis sirtalis) populations throughout the Great Lakes region to evaluate phylogeographic patterns and population structure and to determine whether the distribution of haplotypic variants is related to the post-Pleistocene retreat of the Wisconsinan glacier. The common gartersnake was utilized, as it is believed to have been one of the primary vertebrate invaders of the Great Lakes region following the most recent period of glacial retreat and because it has been a model species for a variety of evolutionary, ecological, behavioral, and physiological studies. Several genetically distinct evolutionary lineages were supported by both genealogical and molecular population genetic analyses, although to different degrees. The geographic distribution of the majority of these lineages is interpreted as reflecting post-glacial recolonization dynamics during the late Pleistocene. These findings generally support previous hypotheses of range expansion in this region.

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.

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.

If Only my Leader Would just Do Something! Passive Leadership Undermines Employee Well-being Through Role Stressors and Psychological Resource Depletion.

PubMed

Barling, Julian; Frone, Michael R

2017-08-01

The goal of this study was to develop and test a sequential mediational model explaining the negative relationship of passive leadership to employee well-being. Based on role stress theory, we posit that passive leadership will predict higher levels of role ambiguity, role conflict and role overload. Invoking Conservation of Resources theory, we further hypothesize that these role stressors will indirectly and negatively influence two aspects of employee well-being, namely overall mental health and overall work attitude, through psychological work fatigue. Using a probability sample of 2467 US workers, structural equation modelling supported the model by showing that role stressors and psychological work fatigue partially mediated the negative relationship between passive leadership and both aspects of employee well-being. The hypothesized, sequential indirect relationships explained 47.9% of the overall relationship between passive leadership and mental health and 26.6% of the overall relationship between passive leadership and overall work attitude. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Sex Role Orientation Across the Adult Life Span.

ERIC Educational Resources Information Center

Zaks, Peggy M.; And Others

It was hypothesized that four different "life lines" would affect sex role orientations, specifically intimacy, parenting, grandparenting, and work. Subjects were 74 men and 43 women, white, upper middle class with a mean education level of 14 years. Each participant completed a demographic questionnaire, the Bem Sex Role Inventory, a…

Characterization of Acinetobacter baumannii biofilm associated components

NASA Astrophysics Data System (ADS)

Brossard, Kari A.

Acinetobacter baumannii is a Gram-negative aerobic coccobaccillus that is a major cause of nosocomial infections worldwide. Infected individuals may develop pneumonia, urinary tract, wound, and other infections that are associated with the use of indwelling medical devices such as catheters and mechanical ventilation. Treatment is difficult because many A. baumannii isolates have developed multi-drug resistance and the bacterium can persist on abiotic surfaces. Persistence and resistance may be due to formation of biofilms, which leads to long-term colonization, evasion of the host immune system and resistance to treatment with antibiotics and disinfectants. While biofilms are complex multifaceted structures, two bacterial components that have been shown to be important in formation and stability are exopolysaccharides (EPS) and the biofilm-associated protein (Bap). An EPS, poly-beta-1,6-N-acetylglucosamine, PNAG, has been described for E. coli and S. epidermidis. PNAG acts as an intercellular adhesin. Production of this adhesin is dependent on the pga/icaABCD locus. We have identified a homologous locus in A. baumannii 307-0294 that is involved in production of an exopolysaccharide, recognized by an anti-PNAG antibody. We hypothesized that the A. baumannii pgaABCD locus plays a role in biofilm formation, and protection against host innate defenses and disinfectants suggesting that PNAG is a possible virulence factor for the organism. The first aim of this thesis will define the pgaABCD locus. We have previously identified Bap, a protein with similarity to those described for S. aureus and we have demonstrated that this protein is involved in maintaining the stability of biofilms on glass. We hypothesized that A. baumannii Bap plays a role in persistence and pathogenesis and is regulated by quorum sensing. In our second aim we will examine the role of Bap in attachment and biofilm formation on medically relevant surfaces and also determine if Bap is involved in epithelial cell surface attachment and invasion. Finally we will determine the effects of quorum sensing on the expression of Bap.

Reward deficiency syndrome in obesity: a preliminary cross-sectional trial with a Genotrim variant.

PubMed

Blum, Kenneth; Chen, Thomas J H; Meshkin, Brian; Downs, B William; Gordon, Cory A; Blum, Seth; Mengucci, Julie F; Braverman, Eric R; Arcuri, Vanessa; Varshavskiy, Michael; Deutsch, Roger; Martinez-Pons, Manuel

2006-01-01

Obesity is the second largest preventable cause of death in the United States. Even though it was classified as a disease in 1985, traditionally, obesity has been treated primarily as a behavioral problem that requires only modifications in diet and exercise. Similar to research on obesity, clinical studies have elucidated the role of biologic and genetic factors in alcoholism and other conditions previously classified as behavioral. These studies showed that behavioral adjustments alone may not address underlying genetic causes. We hypothesize that biologic and genetic factors must be addressed synergistically while behavioral modifications are implemented to adequately treat obese patients. We hypothesize that a predisposition to glucose craving and obesity is due to inadequate dopaminergic activity in the reward center of the brain. This defect drives individuals to engage in activities of behavioral excess, which, in turn, enhance brain dopamine function. Consumption of large quantities of alcohol or carbohydrates (carbohydrate bingeing) stimulates production and usage of dopamine within the brain; the term reward deficiency syndrome (RDS) may be used to categorize such biologic influences on behavior. We propose that a novel approach to nutritional supplementation may be required to target the role of RDS in obesity. In this regard, GenoTrim, a DNA-customized nutritional solution, has been developed and is currently under investigation in several clinical studies. Through its mechanism of action, GenoTrim addresses the genetic influence of RDS on obesity. In this cross-sectional study, 24 subjects were studied after they had completed a case report format questionnaire. For this assessment, we used a novel assessment tool-a path analysis. This statistical regression model is used to (1) examine the effectual relationships between various systems within a multisystem matrix, and (2) measure the contributory roles of those relationships in obesity, enabling the development of targeted and effective therapeutic interventions.

Traditional fire-use, landscape transition, and the legacies of social theory past.

PubMed

Coughlan, Michael R

2015-12-01

Fire-use and the scale and character of its effects on landscapes remain hotly debated in the paleo- and historical-fire literature. Since the second half of the nineteenth century, anthropology and geography have played important roles in providing theoretical propositions and testable hypotheses for advancing understandings of the ecological role of human-fire-use in landscape histories. This article reviews some of the most salient and persistent theoretical propositions and hypotheses concerning the role of humans in historical fire ecology. The review discusses this history in light of current research agendas, such as those offered by pyrogeography. The review suggests that a more theoretically cognizant historical fire ecology should strive to operationalize transdisciplinary theory capable of addressing the role of human variability in the evolutionary history of landscapes. To facilitate this process, researchers should focus attention on integrating more current human ecology theory into transdisciplinary research agendas.

Utility of Krashen's Five Hypotheses in the Saudi Context of Foreign Language Acquisition/Learning

ERIC Educational Resources Information Center

Gulzar, Malik Ajmal; Gulnaz, Fahmeeda; Ijaz, Attiya

2014-01-01

In the last twenty years, the paradigm that has dominated the discipline of language teaching is the SLA theory and Krashen's five hypotheses which are still proving flexible to accommodate earlier reforms. This paper reviews second language acquisition (SLA) theory to establish an understanding of its role in the EFL/ESL classrooms. Other areas…

Learning to Question: The Roles of Multiple Hypotheses, Successive Approximations, Balloons and Toilet Paper in University Science Programs of Southwestern Amazonia

ERIC Educational Resources Information Center

Brown, I. Foster

2008-01-01

Learning to question is essential for determining pathways of conservation and development in southwestern Amazonia during a time of rapid global environmental change. Teaching such an approach in graduate science programs in regional universities can be done using play-acting and simulation exercises. Multiple working hypotheses help students…

Regulatory T cells, maternal-foetal immune tolerance and recurrent miscarriage: new therapeutic challenging opportunities.

PubMed

Alijotas-Reig, Jaume; Melnychuk, Taisiia; Gris, Josep Maria

2015-03-15

Because maternal alloreactive lymphocytes are not depleted during pregnancy, local and/or systemic mechanisms have to play a key role in altering the maternal immune response. Peripheral T regulatory cells (pTregs) at the maternal-foetal interface are necessary in situ to prevent early abortion, but only those pTregs that have been previously exposed to paternal alloantigens. It has been showed that pregnancy selectively stimulates the accumulation of maternal Foxp3(+)CD4(+)CD25(+) (Foxp3Tregs) cells with foetal specificity. Interestingly, after delivery, foetal-specific pTregs persist at elevated levels, maintain tolerance to pre-existing foetal antigen, and rapidly re-accumulate during subsequent pregnancy. pTreg up-regulation could be hypothesized as a possible future therapeutic strategy in humans. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

Light-regulated root gravitropism: a role for, and characterization of, a calcium/calmodulin-dependent protein kinase homolog

NASA Technical Reports Server (NTRS)

Lu, Y. T.; Feldman, L. J.

1997-01-01

Roots of many species grow downward (orthogravitropism) only when illuminated. Previous work suggests that this is a calcium-regulated response and that both calmodulin and calcium/calmodulin-dependent kinases participate in transducing gravity and light stimuli. A genomic sequence has been obtained for a calcium/calmodulin-dependent kinase homolog (MCK1) expressed in root caps, the site of perception for both light and gravity. This homolog consists of 7265 base pairs and contains 11 exons and 10 introns. Since MCK1 is expressed constitutively in both light and dark, it is unlikely that the light directly affects MCK1 expression, though the activity of the protein may be affected by light. In cultivars showing light-regulated gravitropism, we hypothesize that MCK1, or a homolog, functions in establishing the auxin asymmetry necessary for orthogravitropism.

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.

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

Glia initiate brain assembly through non-canonical Chimaerin/Furin axon guidance in C. elegans

PubMed Central

Rapti, Georgia; Li, Chang; Shan, Alan; Lu, Yun; Shaham, Shai

2017-01-01

Brain assembly is hypothesized to begin when pioneer axons extend over non-neuronal cells, forming tracts guiding follower axons. Yet pioneer-neuron identities, their guidance substrates, and their interactions, are not well understood. Here, using time-lapse embryonic imaging, genetics, protein-interaction, and functional studies, we uncover the early events of C. elegans brain assembly. We demonstrate that C. elegans glia are key for assembly initiation, guiding pioneer and follower axons using distinct signals. Pioneer sublateral neurons, with unique growth properties, anatomy, and innervation, cooperate with glia to mediate follower-axon guidance. We further identify a CHIN-1/Chimaerin-KPC-1/Furin double mutant that severely disrupts assembly. CHIN-1/Chimaerin and KPC-1/Furin function non-canonically in glia and pioneer neurons for guidance-cue trafficking. We exploit this bottleneck to define roles for glial Netrin and Semaphorin in pioneer- and follower-axon guidance, respectively, and for glial and pioneer-neuron Flamingo/CELSR in follower-axon navigation. Altogether, our studies reveal previously-unknown glial roles in pioneer-axon guidance, suggesting conserved brain-assembly principles. PMID:28846083

Dynamics of neuronal circuits in addiction: reward, antireward, and emotional memory.

PubMed

Koob, G F

2009-05-01

Drug addiction is conceptualized as chronic, relapsing compulsive use of drugs with significant dysregulation of brain hedonic systems. Compulsive drug use is accompanied by decreased function of brain substrates for drug positive reinforcement and recruitment of brain substrates mediating the negative reinforcement of motivational withdrawal. The neural substrates for motivational withdrawal ("dark side" of addiction) involve recruitment of elements of the extended amygdala and the brain stress systems, including corticotropin-releasing factor and norepinephrine. These changes, combined with decreased reward function, are hypothesized to persist in the form of an allostatic state that forms a powerful motivational background for relapse. Relapse also involves a key role for the basolateral amygdala in mediating the motivational effects of stimuli previously paired with drug seeking and drug motivational withdrawal. The basolateral amygdala has a key role in mediating emotional memories in general. The hypothesis argued here is that brain stress systems activated by the motivational consequences of drug withdrawal can not only form the basis for negative reinforcement that drives drug seeking, but also potentiate associative mechanisms that perpetuate the emotional state and help drive the allostatic state of addiction.

A genome-wide approach accounting for body mass index identifies genetic variants influencing fasting glycemic traits and insulin resistance

PubMed Central

Manning, Alisa K.; Hivert, Marie-France; Scott, Robert A.; Grimsby, Jonna L.; Bouatia-Naji, Nabila; Chen, Han; Rybin, Denis; Liu, Ching-Ti; Bielak, Lawrence F.; Prokopenko, Inga; Amin, Najaf; Barnes, Daniel; Cadby, Gemma; Hottenga, Jouke-Jan; Ingelsson, Erik; Jackson, Anne U.; Johnson, Toby; Kanoni, Stavroula; Ladenvall, Claes; Lagou, Vasiliki; Lahti, Jari; Lecoeur, Cecile; Liu, Yongmei; Martinez-Larrad, Maria Teresa; Montasser, May E.; Navarro, Pau; Perry, John R. B.; Rasmussen-Torvik, Laura J.; Salo, Perttu; Sattar, Naveed; Shungin, Dmitry; Strawbridge, Rona J.; Tanaka, Toshiko; van Duijn, Cornelia M.; An, Ping; de Andrade, Mariza; Andrews, Jeanette S.; Aspelund, Thor; Atalay, Mustafa; Aulchenko, Yurii; Balkau, Beverley; Bandinelli, Stefania; Beckmann, Jacques S.; Beilby, John P.; Bellis, Claire; Bergman, Richard N.; Blangero, John; Boban, Mladen; Boehnke, Michael; Boerwinkle, Eric; Bonnycastle, Lori L.; Boomsma, Dorret I.; Borecki, Ingrid B.; Böttcher, Yvonne; Bouchard, Claude; Brunner, Eric; Budimir, Danijela; Campbell, Harry; Carlson, Olga; Chines, Peter S.; Clarke, Robert; Collins, Francis S.; Corbatón-Anchuelo, Arturo; Couper, David; de Faire, Ulf; Dedoussis, George V; Deloukas, Panos; Dimitriou, Maria; Egan, Josephine M; Eiriksdottir, Gudny; Erdos, Michael R.; Eriksson, Johan G.; Eury, Elodie; Ferrucci, Luigi; Ford, Ian; Forouhi, Nita G.; Fox, Caroline S; Franzosi, Maria Grazia; Franks, Paul W; Frayling, Timothy M; Froguel, Philippe; Galan, Pilar; de Geus, Eco; Gigante, Bruna; Glazer, Nicole L.; Goel, Anuj; Groop, Leif; Gudnason, Vilmundur; Hallmans, Göran; Hamsten, Anders; Hansson, Ola; Harris, Tamara B.; Hayward, Caroline; Heath, Simon; Hercberg, Serge; Hicks, Andrew A.; Hingorani, Aroon; Hofman, Albert; Hui, Jennie; Hung, Joseph; Jarvelin, Marjo Riitta; Jhun, Min A.; Johnson, Paul C.D.; Jukema, J Wouter; Jula, Antti; Kao, W.H.; Kaprio, Jaakko; Kardia, Sharon L. R.; Keinanen-Kiukaanniemi, Sirkka; Kivimaki, Mika; Kolcic, Ivana; Kovacs, Peter; Kumari, Meena; Kuusisto, Johanna; Kyvik, Kirsten Ohm; Laakso, Markku; Lakka, Timo; Lannfelt, Lars; Lathrop, G Mark; Launer, Lenore J.; Leander, Karin; Li, Guo; Lind, Lars; Lindstrom, Jaana; Lobbens, Stéphane; Loos, Ruth J. F.; Luan, Jian’an; Lyssenko, Valeriya; Mägi, Reedik; Magnusson, Patrik K. E.; Marmot, Michael; Meneton, Pierre; Mohlke, Karen L.; Mooser, Vincent; Morken, Mario A.; Miljkovic, Iva; Narisu, Narisu; O’Connell, Jeff; Ong, Ken K.; Oostra, Ben A.; Palmer, Lyle J.; Palotie, Aarno; Pankow, James S.; Peden, John F.; Pedersen, Nancy L.; Pehlic, Marina; Peltonen, Leena; Penninx, Brenda; Pericic, Marijana; Perola, Markus; Perusse, Louis; Peyser, Patricia A; Polasek, Ozren; Pramstaller, Peter P.; Province, Michael A.; Räikkönen, Katri; Rauramaa, Rainer; Rehnberg, Emil; Rice, Ken; Rotter, Jerome I.; Rudan, Igor; Ruokonen, Aimo; Saaristo, Timo; Sabater-Lleal, Maria; Salomaa, Veikko; Savage, David B.; Saxena, Richa; Schwarz, Peter; Seedorf, Udo; Sennblad, Bengt; Serrano-Rios, Manuel; Shuldiner, Alan R.; Sijbrands, Eric J.G.; Siscovick, David S.; Smit, Johannes H.; Small, Kerrin S.; Smith, Nicholas L.; Smith, Albert Vernon; Stančáková, Alena; Stirrups, Kathleen; Stumvoll, Michael; Sun, Yan V.; Swift, Amy J.; Tönjes, Anke; Tuomilehto, Jaakko; Trompet, Stella; Uitterlinden, Andre G.; Uusitupa, Matti; Vikström, Max; Vitart, Veronique; Vohl, Marie-Claude; Voight, Benjamin F.; Vollenweider, Peter; Waeber, Gerard; Waterworth, Dawn M; Watkins, Hugh; Wheeler, Eleanor; Widen, Elisabeth; Wild, Sarah H.; Willems, Sara M.; Willemsen, Gonneke; Wilson, James F.; Witteman, Jacqueline C.M.; Wright, Alan F.; Yaghootkar, Hanieh; Zelenika, Diana; Zemunik, Tatijana; Zgaga, Lina; Wareham, Nicholas J.; McCarthy, Mark I.; Barroso, Ines; Watanabe, Richard M.; Florez, Jose C.; Dupuis, Josée; Meigs, James B.; Langenberg, Claudia

2013-01-01

Recent genome-wide association studies have described many loci implicated in type 2 diabetes (T2D) pathophysiology and beta-cell dysfunction, but contributed little to our understanding of the genetic basis of insulin resistance. We hypothesized that genes implicated in insulin resistance pathways may be uncovered by accounting for differences in body mass index (BMI) and potential interaction between BMI and genetic variants. We applied a novel joint meta-analytical approach to test associations with fasting insulin (FI) and glucose (FG) on a genome-wide scale. We present six previously unknown FI loci at P<5×10−8 in combined discovery and follow-up analyses of 52 studies comprising up to 96,496non-diabetic individuals. Risk variants were associated with higher triglyceride and lower HDL cholesterol levels, suggestive of a role for these FI loci in insulin resistance pathways. The localization of these additional loci will aid further characterization of the role of insulin resistance in T2D pathophysiology. PMID:22581228

Thermal actuation in TRPV1: Role of embedded lipids and intracellular domains.

PubMed

Melnick, Corey; Kaviany, Massoud

2018-05-07

The transient response potential cation channel TRPV1 responds to high temperature, but many of the mechanisms driving its thermal actuation remain unclear. Its recently resolved structure has enabled a number of molecular dynamics (MD) studies focused on illuminating these mechanisms. We add to these efforts by performing the first all-atom MD simulations of its most recently resolved structure at different temperatures. While the complete, thermally induced transition of TRPV1 from its closed to open configuration remains elusive, our analysis of the hydrogen bonding networks, thermodynamics, hydration, and principal components of motion provide a wealth of information on the mechanisms which initiate or influence the thermal opening in TRPV1. In particular, we (i) support the previously proposed mechanism driving thermal actuation in the extracellular pore of TRPV1, (ii) present new hypotheses regarding the thermal actuation in the C-terminal and adjacent linker domains, and (iii) support and build upon the existing hypothesis regarding the role of the vanilloid binding pocket and lipids embedded therein. Copyright © 2018 Elsevier Ltd. All rights reserved.

[The role of the jumping to conclusion bias in delusions formation].

PubMed

Rózycka, Jagoda; Prochwicz, Katarzyna

2013-01-01

The results of many researches indicate that individuals with delusions reveal the reasoning bias. In probabilistic reasoning tasks they reveal hastiness in decision-making. The individuals with delusions request less information than non-deluded individuals, even if additional data is easily available. What is more, they also prove to be convinced to a greater extend of having made the right decision. This finding has been replicated by a number of studies. However, the previous researches have not confirmed the origins of 'jumping to conclusion' bias, and its role in the process of forming delusions has not been yet confirmed. The article in question contains the review of the results of the jumping to conclusion bias in people with delusions. It discusses the main hypotheses explaining the relations between the hasty decision making and the delusions formation. The article also deals with the specifics of 'jumping to conclusion' bias in case of individuals with delusions, as well as summarizes its relation to factors such as the level of intelligence or the intensity of delusion.

New insights into the role of motion and form vision in neurodevelopmental disorders.

PubMed

Johnston, Richard; Pitchford, Nicola J; Roach, Neil W; Ledgeway, Timothy

2017-12-01

A selective deficit in processing the global (overall) motion, but not form, of spatially extensive objects in the visual scene is frequently associated with several neurodevelopmental disorders, including preterm birth. Existing theories that proposed to explain the origin of this visual impairment are, however, challenged by recent research. In this review, we explore alternative hypotheses for why deficits in the processing of global motion, relative to global form, might arise. We describe recent evidence that has utilised novel tasks of global motion and global form to elucidate the underlying nature of the visual deficit reported in different neurodevelopmental disorders. We also examine the role of IQ and how the sex of an individual can influence performance on these tasks, as these are factors that are associated with performance on global motion tasks, but have not been systematically controlled for in previous studies exploring visual processing in clinical populations. Finally, we suggest that a new theoretical framework is needed for visual processing in neurodevelopmental disorders and present recommendations for future research. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

An endocannabinoid hypothesis of drug reward and drug addiction.

PubMed

Onaivi, Emmanuel S

2008-10-01

Pharmacologic treatment of drug and alcohol dependency has largely been disappointing, and new therapeutic targets and hypotheses are needed. There is accumulating evidence indicating a central role for the previously unknown but ubiquitous endocannabinoid physiological control system (EPCS) in the regulation of the rewarding effects of abused substances. Thus an endocannabinoid hypothesis of drug reward is postulated. Endocannabinoids mediate retrograde signaling in neuronal tissues and are involved in the regulation of synaptic transmission to suppress neurotransmitter release by the presynaptic cannabinoid receptors (CB-Rs). This powerful modulatory action on synaptic transmission has significant functional implications and interactions with the effects of abused substances. Our data, along with those from other investigators, provide strong new evidence for a role for EPCS modulation in the effects of drugs of abuse, and specifically for involvement of cannabinoid receptors in the neural basis of addiction. Cannabinoids and endocannabinoids appear to be involved in adding to the rewarding effects of addictive substances, including, nicotine, opiates, alcohol, cocaine, and BDZs. The results suggest that the EPCS may be an important natural regulatory mechanism for drug reward and a target for the treatment of addictive disorders.

Heart rate variability predicts alcohol craving in alcohol dependent outpatients: further evidence for HRV as a psychophysiological marker of self-regulation.

PubMed

Quintana, Daniel S; Guastella, Adam J; McGregor, Iain S; Hickie, Ian B; Kemp, Andrew H

2013-09-01

Past research has highlighted an important role of the autonomic nervous system in alcohol dependence and capacity for self-regulation. While previous studies have examined alcohol dependent inpatients, it remains unclear whether resting-state HRV, a potential psychophysiological marker of ones capacity for self-regulation, is related to craving in patients who currently consume alcohol. Thus, the aim of the present study was to determine whether HRV predicts alcohol craving in dependent individuals in the community. Resting-state HRV and alcohol craving, as indexed by the obsessive compulsive drinking scale, were assessed in 26 alcohol dependent outpatients. Results supported hypotheses indicating that HRV accounts for an additional 12.1% of the variance in craving after controlling for age, anxiety and levels of alcohol consumption. Here we show for the first time that resting-state HRV predicts craving in alcohol dependent outpatients. Results provide important new evidence for a role of the autonomic nervous system in the maintenance of dependence disorders. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Bone tissue engineering: the role of interstitial fluid flow

NASA Technical Reports Server (NTRS)

Hillsley, M. V.; Frangos, J. A.

1994-01-01

It is well established that vascularization is required for effective bone healing. This implies that blood flow and interstitial fluid (ISF) flow are required for healing and maintenance of bone. The fact that changes in bone blood flow and ISF flow are associated with changes in bone remodeling and formation support this theory. ISF flow in bone results from transcortical pressure gradients produced by vascular and hydrostatic pressure, and mechanical loading. Conditions observed to alter flow rates include increases in venous pressure in hypertension, fluid shifts occurring in bedrest and microgravity, increases in vascularization during the injury-healing response, and mechanical compression and bending of bone during exercise. These conditions also induce changes in bone remodeling. Previously, we hypothesized that interstitial fluid flow in bone, and in particular fluid shear stress, serves to mediate signal transduction in mechanical loading- and injury-induced remodeling. In addition, we proposed that a lack or decrease of ISF flow results in the bone loss observed in disuse and microgravity. The purpose of this article is to review ISF flow in bone and its role in osteogenesis.

Maximum saliency bias in binocular fusion

NASA Astrophysics Data System (ADS)

Lu, Yuhao; Stafford, Tom; Fox, Charles

2016-07-01

Subjective experience at any instant consists of a single ("unitary"), coherent interpretation of sense data rather than a "Bayesian blur" of alternatives. However, computation of Bayes-optimal actions has no role for unitary perception, instead being required to integrate over every possible action-percept pair to maximise expected utility. So what is the role of unitary coherent percepts, and how are they computed? Recent work provided objective evidence for non-Bayes-optimal, unitary coherent, perception and action in humans; and further suggested that the percept selected is not the maximum a posteriori percept but is instead affected by utility. The present study uses a binocular fusion task first to reproduce the same effect in a new domain, and second, to test multiple hypotheses about exactly how utility may affect the percept. After accounting for high experimental noise, it finds that both Bayes optimality (maximise expected utility) and the previously proposed maximum-utility hypothesis are outperformed in fitting the data by a modified maximum-salience hypothesis, using unsigned utility magnitudes in place of signed utilities in the bias function.

The Relation between Parental Involvement and Math Anxiety: Implications for Mathematics Achievement

ERIC Educational Resources Information Center

Roberts, Steven O.; Vukovic, Rose K.

2011-01-01

Previous research served as the platform for this study's research question: Does math anxiety mediate the relation between parental involvement and mathematics achievement? The primary purpose of this study was to examine this mediation model in a sample of at-risk second graders. Due to previous research, the investigators hypothesized that math…

Creating One's Reality: The Interaction of Politics Perceptions and Enactment Behavior.

PubMed

Frieder, Rachel E; Ma, Shuang Sara; Hochwarter, Wayne A

2016-01-01

The current study investigated the previously unexamined relationship between politics perceptions and employee enactment behavior. Consistent with previous job stress and sense-making research, we hypothesized that individuals reporting low levels of enactment behaviors would be more adversely affected by politics perceptions than those who engaged in high levels of enactment behavior. Results across two samples provided strong support for the hypothesized relationships. Specifically, employees who reported low levels of enactment behavior experienced less satisfaction, less person-environment fit, and reported lower levels of effort when faced with highly political environments. Conversely, levels of satisfaction and person-environment fit perceptions of individuals reporting high levels of enactment behaviors were largely unaffected by highly political contexts. Implications of these findings, strengths and limitations, and avenues for future research are provided.

Examining the Relationship Between Trauma Centrality and Posttraumatic Stress Disorder Symptoms: A Moderated Mediation Approach

PubMed Central

Park, Crystal L.; Chaudoir, Stephenie R.

2016-01-01

Background and Objectives The degree to which a traumatic event is seen as central to one's sense of self (trauma centrality) has been associated with posttraumatic stress disorder (PTSD) symptoms. Based on cognitive models of PTSD that highlight the role that maladaptive appraisals play in generating PTSD symptoms, we hypothesized that appraising a trauma as violating one's core beliefs and goals mediates the link between trauma centrality and PTSD symptoms. Further, we reasoned that coping ability moderates the direct and indirect link as those with better coping ability will have more adaptive appraisals. Design Hypotheses were examined in a cross-sectional sample of 367 undergraduates who have experienced a traumatic event. Methods Data were collected via an online survey. Results Overall, results of the moderated mediation analysis were consistent with the hypothesized mediating role for appraised violations and moderating role for coping ability. Conclusions Findings highlight the importance of considering individual differences and trauma appraisals in understanding the relationship between trauma centrality and PTSD — trauma centrality may be related to PTSD symptoms more so among people with poorer coping ability who appraise a trauma as violating their core beliefs and goals. PMID:27458331

Exploration as a mediator of the relation between the attainment of motor milestones and the development of spatial cognition and spatial language.

PubMed

Oudgenoeg-Paz, Ora; Leseman, Paul P M; Volman, M Chiel J M

2015-09-01

The embodied-cognition approach views cognition and language as grounded in daily sensorimotor child-environment interactions. Therefore, the attainment of motor milestones is expected to play a role in cognitive-linguistic development. Early attainment of unsupported sitting and independent walking indeed predict better spatial cognition and language at later ages. However, evidence linking these milestones with the development of spatial language and evidence regarding factors that might mediate this relation are scarce. The current study examined whether exploration of spatial-relational object properties (e.g., the possibility of containing or stacking) and exploration of the space through self-locomotion mediate the effect of, respectively, age of sitting and age of walking on spatial cognition and spatial language. Thus, we hypothesized that an earlier age of sitting and walking predicts, respectively, higher levels of spatial-relational object exploration and exploration through self-locomotion, which in turn, predict better spatial cognition and spatial language at later ages. Fifty-nine Dutch children took part in a longitudinal study. A combination of tests, observations, and parental reports was used to measure motor development, exploratory behavior (age 20 months), spatial memory (age 24 months), spatial processing (age 32 months), and spatial language (age 36 months). Results show that attainment of sitting predicted spatial memory and spatial language, but spatial-relational object exploration did not mediate these effects. Attainment of independent walking predicted spatial processing and spatial language, and exploration through self-locomotion (partially) mediated these relations. These findings extend previous work and provide partial support for the hypotheses about the mediating role of exploration. (c) 2015 APA, all rights reserved).

Fluorescent proteins function as a prey attractant: experimental evidence from the hydromedusa Olindias formosus and other marine organisms

PubMed Central

Haddock, Steven H. D.; Dunn, Casey W.

2015-01-01

ABSTRACT Although proteins in the green fluorescent protein family (GFPs) have been discovered in a wide array of taxa, their ecological functions in these organisms remain unclear. Many hypothesized roles are related to modifying bioluminescence spectra or modulating the light regime for algal symbionts, but these do not explain the presence of GFPs in animals that are non-luminous and non-symbiotic. Other hypothesized functions are unrelated to the visual signals themselves, including stress responses and antioxidant roles, but these cannot explain the localization of fluorescence in particular structures on the animals. Here we tested the hypothesis that fluorescence might serve to attract prey. In laboratory experiments, the predator was the hydromedusa Olindias formosus (previously known as O. formosa), which has fluorescent and pigmented patches on the tips of its tentacles. The prey, juvenile rockfishes in the genus Sebastes, were significantly more attracted (P<1×10−5) to the medusa's tentacles under lighting conditions where fluorescence was excited and tentacle tips were visible above the background. The fish did not respond significantly when treatments did not include fluorescent structures or took place under yellow or white lights, which did not generate fluorescence visible above the ambient light. Furthermore, underwater observations of the behavior of fishes when presented with a brightly illuminated point showed a strong attraction to this visual stimulus. In situ observations also provided evidence for fluorescent lures as supernormal stimuli in several other marine animals, including the siphonophore Rhizophysa eysenhardti. Our results support the idea that fluorescent structures can serve as prey attractants, thus providing a potential function for GFPs and other fluorescent proteins in a diverse range of organisms. PMID:26231627

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

The ankyrin-3 gene is associated with posttraumatic stress disorder and externalizing comorbidity

PubMed Central

Logue, Mark W.; Solovieff, Nadia; Leussis, Melanie P.; Wolf, Erika J.; Melista, Efi; Baldwin, Clinton; Koenen, Karestan C.; Petryshen, Tracey; Miller, Mark W.

2013-01-01

Background The ankyrin 3 gene (ANK3) produces the ankyrin G protein that plays an integral role in regulating neuronal activity. Previous studies have linked ANK3 to bipolar disorder and schizophrenia. A recent mouse study suggests that ANK3 may regulate behavioral disinhibition and stress reactivity. This led us to hypothesize that ANK3 might also be associated with stress-related psychopathology such as posttraumatic stress disorder (PTSD), as well as disorders of the externalizing spectrum such as antisocial personality disorder and substance-related disorders that are etiologically linked to impulsivity and temperamental disinhibition. Methods We examined the possibility of association between ANK3 SNPs and both PTSD and externalizing (defined by a factor score representing a composite of adult antisociality and substance abuse) in a cohort of white non-Hispanic combat veterans and their intimate partners (N=554). Initially, we focused on rs9804190— a SNP previously reported to be associated with bipolar disorder, schizophrenia, and ankyrin G expression in brain. Then we examined 358 additional ANK3 SNPs utilizing a multiple-testing correction. Results rs9804190 was associated with both externalizing and PTSD (p=0.028 and p=0.042 respectively). Analysis of other ANK3 SNPs identified several that were more strongly associated with either trait. The most significant association with externalizing was observed at rs1049862 (p=0.00040, pcorrected=0.60). The most significant association with PTSD (p=0.00060, pcorrected=0.045) was found with three SNPs in complete linkage disequilibrium (LD)—rs28932171, rs11599164, and rs17208576. Conclusions These findings support a role of ANK3 in risk of stress-related and externalizing disorders, beyond its previous associations with bipolar disorder and schizophrenia. PMID:23796624

Beneficial Effects of Sodium Phenylbutyrate Administration during Infection with Salmonella enterica Serovar Typhimurium.

PubMed

Jellbauer, Stefan; Perez Lopez, Araceli; Behnsen, Judith; Gao, Nina; Nguyen, Thao; Murphy, Clodagh; Edwards, Robert A; Raffatellu, Manuela

2016-09-01

Sodium phenylbutyrate (PBA) is a derivative of the short-chain fatty acid butyrate and is approved for treatment of urea cycle disorders and progressive familial intrahepatic cholestasis type 2. Previously known functions include histone deacetylase inhibitor, endoplasmic reticulum stress inhibitor, ammonia sink, and chemical chaperone. Here, we show that PBA has a previously undiscovered protective role in host mucosal defense during infection. Administration of PBA to Taconic mice resulted in the increase of intestinal Lactobacillales and segmented filamentous bacteria (SFB), as well as an increase of interleukin 17 (IL-17) production by intestinal cells. This effect was not observed in Jackson Laboratory mice, which are not colonized with SFB. Because previous studies showed that IL-17 plays a protective role during infection with mucosal pathogens, we hypothesized that Taconic mice treated with PBA would be more resistant to infection with Salmonella enterica serovar Typhimurium (S Typhimurium). By using the streptomycin-treated mouse model, we found that Taconic mice treated with PBA exhibited significantly lower S Typhimurium intestinal colonization and dissemination to the reticuloendothelial system, as well as lower levels of inflammation. The lower levels of S Typhimurium gut colonization and intestinal inflammation were not observed in Jackson Laboratory mice. Although PBA had no direct effect on bacterial replication, its administration reduced S Typhimurium epithelial cell invasion and lowered the induction of the proinflammatory cytokine IL-23 in macrophage-like cells. These effects likely contributed to the better outcome of infection in PBA-treated mice. Overall, our results suggest that PBA induces changes in the microbiota and in the mucosal immune response that can be beneficial to the host during infection with S Typhimurium and possibly other enteric pathogens. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Beneficial Effects of Sodium Phenylbutyrate Administration during Infection with Salmonella enterica Serovar Typhimurium

PubMed Central

Jellbauer, Stefan; Perez Lopez, Araceli; Behnsen, Judith; Gao, Nina; Nguyen, Thao; Murphy, Clodagh; Edwards, Robert A.

2016-01-01

Sodium phenylbutyrate (PBA) is a derivative of the short-chain fatty acid butyrate and is approved for treatment of urea cycle disorders and progressive familial intrahepatic cholestasis type 2. Previously known functions include histone deacetylase inhibitor, endoplasmic reticulum stress inhibitor, ammonia sink, and chemical chaperone. Here, we show that PBA has a previously undiscovered protective role in host mucosal defense during infection. Administration of PBA to Taconic mice resulted in the increase of intestinal Lactobacillales and segmented filamentous bacteria (SFB), as well as an increase of interleukin 17 (IL-17) production by intestinal cells. This effect was not observed in Jackson Laboratory mice, which are not colonized with SFB. Because previous studies showed that IL-17 plays a protective role during infection with mucosal pathogens, we hypothesized that Taconic mice treated with PBA would be more resistant to infection with Salmonella enterica serovar Typhimurium (S. Typhimurium). By using the streptomycin-treated mouse model, we found that Taconic mice treated with PBA exhibited significantly lower S. Typhimurium intestinal colonization and dissemination to the reticuloendothelial system, as well as lower levels of inflammation. The lower levels of S. Typhimurium gut colonization and intestinal inflammation were not observed in Jackson Laboratory mice. Although PBA had no direct effect on bacterial replication, its administration reduced S. Typhimurium epithelial cell invasion and lowered the induction of the proinflammatory cytokine IL-23 in macrophage-like cells. These effects likely contributed to the better outcome of infection in PBA-treated mice. Overall, our results suggest that PBA induces changes in the microbiota and in the mucosal immune response that can be beneficial to the host during infection with S. Typhimurium and possibly other enteric pathogens. PMID:27382022

Does prediction error drive one-shot declarative learning?

PubMed

Greve, Andrea; Cooper, Elisa; Kaula, Alexander; Anderson, Michael C; Henson, Richard

2017-06-01

The role of prediction error (PE) in driving learning is well-established in fields such as classical and instrumental conditioning, reward learning and procedural memory; however, its role in human one-shot declarative encoding is less clear. According to one recent hypothesis, PE reflects the divergence between two probability distributions: one reflecting the prior probability (from previous experiences) and the other reflecting the sensory evidence (from the current experience). Assuming unimodal probability distributions, PE can be manipulated in three ways: (1) the distance between the mode of the prior and evidence, (2) the precision of the prior, and (3) the precision of the evidence. We tested these three manipulations across five experiments, in terms of peoples' ability to encode a single presentation of a scene-item pairing as a function of previous exposures to that scene and/or item. Memory was probed by presenting the scene together with three choices for the previously paired item, in which the two foil items were from other pairings within the same condition as the target item. In Experiment 1, we manipulated the evidence to be either consistent or inconsistent with prior expectations, predicting PE to be larger, and hence memory better, when the new pairing was inconsistent. In Experiments 2a-c, we manipulated the precision of the priors, predicting better memory for a new pairing when the (inconsistent) priors were more precise. In Experiment 3, we manipulated both visual noise and prior exposure for unfamiliar faces, before pairing them with scenes, predicting better memory when the sensory evidence was more precise. In all experiments, the PE hypotheses were supported. We discuss alternative explanations of individual experiments, and conclude the Predictive Interactive Multiple Memory Signals (PIMMS) framework provides the most parsimonious account of the full pattern of results.

Sex-Role Traditionalism, Assertiveness, and Symptoms of Puerto Rican Women Living in the United States.

ERIC Educational Resources Information Center

Soto, Elaine; Shaver, Phillip

1982-01-01

A questionnaire containing objectively scored measures of migration history, educational attainment, sex-role traditionalism, assertiveness, and symptoms of mental and physical illness was completed by 278 Puerto Rican women (aged 18-55) living in New York City. As hypothesized, sex-role traditionalism correlated negatively with symptoms. (Author)

Attitude Bolstering Following Self-Induced Value Discrepancy.

ERIC Educational Resources Information Center

Sherman, Steven J.; Gorkln, Larry

To study the effects of behaving inconsistently with a central attitude, subjects (N=77) filled out a "Contemporary Social Issues Questionnaire," and then completed a sex-role or non-sex-role logic problem. It was hypothesized that subjects who score high on a feminism scale and who fail to solve a sex-role problem, thus demonstrating…

Marital Satisfaction in Later Life: The Effects of Nonmarital Roles.

ERIC Educational Resources Information Center

Lee, Gary R.

1988-01-01

Predicted that marital satisfaction would be higher in later stages of life cycle because of diminishing demands of nonmarital roles. Data from 2,327 older married persons showed that departure of children was associated with higher levels of marital satisfaction; other hypotheses based on role overload theory received no support and were…

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.

Histone Deacetylase Inhibition Induces Odor Preference Memory Extension and Maintains Enhanced AMPA Receptor Expression in the Rat Pup Model

ERIC Educational Resources Information Center

Bhattacharya, Sriya; Mukherjee, Bandhan; Doré, Jules J. E.; Yuan, Qi; Harley, Carolyn W.; McLean, John H.

2017-01-01

Histone deacetylase (HDAC) plays a role in synaptic plasticity and long-term memory formation. We hypothesized that trichostatin-A (TSA), an HDAC inhibitor, would promote long-term odor preference memory and maintain enhanced GluA1 receptor levels that have been hypothesized to support memory. We used an early odor preference learning model in…

Public views on the role of government in funding and delivering health services.

PubMed

Vilhjalmsson, Runar

2016-07-01

Public surveys in socialized health systems indicate strong support for the role of government in health care, although different views can be detected. The study considers the public's views on public versus private funding and delivery of health services. The study is based on a representative national sample of 1532 Icelandic adults, aged 18 and older, who participated in a national public issues survey. Respondents were asked about government spending on health care and whether the government or private parties should deliver health services. The great majority of respondents thought that the government should spend more on health care, and should be the primary provider of care. Lower age, female gender, countryside residence, and expected high use of health care were related to greater support for governmental funding. Furthermore, countryside residence, less education, lower income, not being a governmental health worker, expected high health care use, and left-wing political ideology were all related to greater support for governmental delivery of health care. CONCLUSIONS DESPITE SOCIODEMOGRAPHIC VARIATIONS, THE STUDY FINDS STRONG OVERALL SUPPORT FOR THE ROLE OF GOVERNMENT IN FUNDING AND DELIVERING HEALTH CARE PREVIOUS PERSPECTIVES AND HYPOTHESES OF WELFARE STATE ENDORSEMENT RECEIVED MIXED SUPPORT, SUGGESTING THAT FURTHER THEORETICAL AND EMPIRICAL WORK IS NEEDED TO BETTER ACCOUNT FOR PUBLIC VIEWS ON THE ROLE OF GOVERNMENT IN HEALTH CARE. © 2016 the Nordic Societies of Public Health.

Three Ways in Which Midline Regions Contribute to Self-Evaluation

PubMed Central

Flagan, Taru; Beer, Jennifer S.

2013-01-01

An integration of existing research and newly conducted psychophysiological interaction (PPI) connectivity analyses suggest a new framework for understanding the contribution of midline regions to social cognition. Recent meta-analyses suggest that there are no midline regions that are exclusively associated with self-processing. Whereas medial prefrontal cortex (MPFC) is broadly modulated by self-processing, subdivisions within MPFC are differentially modulated by the evaluation of close others (ventral MPFC: BA 10/32) and the evaluation of other social targets (dorsal MPFC: BA 9/32). The role of DMPFC in social cognition may also be less uniquely social than previously thought; it may be better characterized as a region that indexes certainty about evaluation rather than previously considered social mechanisms (i.e., correction of self-projection). VMPFC, a region often described as an important mediator of socioemotional significance, may instead perform a more cognitive role by reflecting the type of information brought to bear on evaluations of people we know well. Furthermore, the new framework moves beyond MPFC and hypothesizes that two other midline regions, ventral anterior cingulate cortex (VACC: BA 25) and medial orbitofrontal cortex (MOFC: BA 11), aid motivational influences on social cognition. Despite the central role of motivation in psychological models of self-perception, neural models have largely ignored the topic. Positive connectivity between VACC and MOFC may mediate bottom-up sensitivity to information based on its potential for helping us evaluate ourselves or others the way we want. As connectivity becomes more positive with striatum and less positive with middle frontal gyrus (BA 9/44), MOFC mediates top-down motivational influences by adjusting the standards we bring to bear on evaluations of ourselves and other people. PMID:23935580

Role of Dynamics in the Autoinhibition and Activation of the Hyperpolarization-activated Cyclic Nucleotide-modulated (HCN) Ion Channels*♦

PubMed Central

VanSchouwen, Bryan; Akimoto, Madoka; Sayadi, Maryam; Fogolari, Federico; Melacini, Giuseppe

2015-01-01

The hyperpolarization-activated cyclic nucleotide-modulated (HCN) ion channels control rhythmicity in neurons and cardiomyocytes. Cyclic AMP allosterically modulates HCN through the cAMP-dependent formation of a tetrameric gating ring spanning the intracellular region (IR) of HCN, to which cAMP binds. Although the apo versus holo conformational changes of the cAMP-binding domain (CBD) have been previously mapped, only limited information is currently available on the HCN IR dynamics, which have been hypothesized to play a critical role in the cAMP-dependent gating of HCN. Here, using molecular dynamics simulations validated and complemented by experimental NMR and CD data, we comparatively analyze HCN IR dynamics in the four states of the thermodynamic cycle arising from the coupling between cAMP binding and tetramerization equilibria. This extensive set of molecular dynamics trajectories captures the active-to-inactive transition that had remained elusive for other CBDs, and it provides unprecedented insight on the role of IR dynamics in HCN autoinhibition and its release by cAMP. Specifically, the IR tetramerization domain becomes more flexible in the monomeric states, removing steric clashes that the apo-CDB structure would otherwise impose. Furthermore, the simulations reveal that the active/inactive structural transition for the apo-monomeric CBD occurs through a manifold of pathways that are more divergent than previously anticipated. Upon cAMP binding, these pathways become disallowed, pre-confining the CBD conformational ensemble to a tetramer-compatible state. This conformational confinement primes the IR for tetramerization and thus provides a model of how cAMP controls HCN channel gating. PMID:25944904

Invasive Congeners Differ in Successional Impacts across Space and Time

PubMed Central

David, Aaron S.; Zarnetske, Phoebe L.; Hacker, Sally D.; Ruggiero, Peter; Biel, Reuben G.; Seabloom, Eric W.

2015-01-01

Invasive species can alter the succession of ecological communities because they are often adapted to the disturbed conditions that initiate succession. The extent to which this occurs may depend on how widely they are distributed across environmental gradients and how long they persist over the course of succession. We focus on plant communities of the USA Pacific Northwest coastal dunes, where disturbance is characterized by changes in sediment supply, and the plant community is dominated by two introduced grasses – the long-established Ammophila arenaria and the currently invading A. breviligulata. Previous studies showed that A. breviligulata has replaced A. arenaria and reduced community diversity. We hypothesize that this is largely due to A. breviligulata occupying a wider distribution across spatial environmental gradients and persisting in later-successional habitat than A. arenaria. We used multi-decadal chronosequences and a resurvey study spanning 2 decades to characterize distributions of both species across space and time, and investigated how these distributions were associated with changes in the plant community. The invading A. breviligulata persisted longer and occupied a wider spatial distribution across the dune, and this corresponded with a reduction in plant species richness and native cover. Furthermore, backdunes previously dominated by A. arenaria switched to being dominated by A. breviligulata, forest, or developed land over a 23-yr period. Ammophila breviligulata likely invades by displacing A. arenaria, and reduces plant diversity by maintaining its dominance into later successional backdunes. Our results suggest distinct roles in succession, with A. arenaria playing a more classically facilitative role and A. breviligulata a more inhibitory role. Differential abilities of closely-related invasive species to persist through time and occupy heterogeneous environments allows for distinct impacts on communities during succession. PMID:25658824

College men's intimate partner violence attitudes: contributions of adult attachment and gender role stress.

PubMed

McDermott, Ryon C; Lopez, Frederick G

2013-01-01

Primary prevention of men's intimate partner violence (IPV) toward women in dating relationships is an important area of psychological inquiry and a significant concern for counselors working with college student populations. Previous research has identified that certain beliefs condoning or accepting physical, sexual, and psychological violence in relationships are key risk factors for IPV perpetration; however, comparatively few studies have examined the social and relational variables related to IPV acceptance attitudes. In the present study, we proposed and tested a structural model examining the combined contributions of adult attachment dimensions (i.e., attachment anxiety and attachment avoidance) and masculine gender role stress in the prediction of IPV acceptance attitudes in a large sample of college men (N = 419). We hypothesized that the relationship between attachment insecurity and IPV acceptance attitudes would be partially mediated by men's gender role stress. A partially mediated model produced the best indices of model fit, accounting for 31% of the variance in an IPV acceptance attitudes latent variable. A bootstrapping procedure confirmed the significance of mediation effects. These results suggest that aspects of adult attachment insecurity are associated with tendencies to experience stress from violations of rigidly internalized traditional male role norms, which, in turn, are associated with acceptance of IPV. Findings are further discussed in relation to adult attachment theory (Mikulincer & Shaver, 2007), gender role strain theory (Pleck, 1995), and their implications for IPV prevention in college student populations. PsycINFO Database Record (c) 2013 APA, all rights reserved.

Empowering leadership and job crafting: The role of employee optimism.

PubMed

Thun, Sylvi; Bakker, Arnold B

2018-06-08

The objective of this study was to test the relationship between empowering leadership and job crafting and to examine the moderating role of optimism as a personal resource. We hypothesized that the association between empowering leadership and job crafting would be stronger for employees with high (vs. low) levels of optimism. A total of 331 Norwegian workers from a variety of occupations participated in our study. Results of structural equation modelling analysis generally supported our hypotheses. Empowering leadership was positively related to 3 of the 4 job crafting strategies investigated (increasing structural job resources, increasing social job resources, and increasing challenging job demands; but not reducing hindrance job demands). Moreover, as hypothesized, optimism strengthened the empowering leadership-job crafting relationship for increasing structural resources and increasing challenging demands. The results suggest that empowering leadership is an important antecedent of job crafting strategies, except for reducing hindrance demands. The implications of these findings are discussed. Copyright © 2018 John Wiley & Sons, Ltd.

The role of biotic forces in driving macroevolution: beyond the Red Queen

PubMed Central

Voje, Kjetil L.; Holen, Øistein H.; Liow, Lee Hsiang; Stenseth, Nils Chr.

2015-01-01

A multitude of hypotheses claim that abiotic factors are the main drivers of macroevolutionary change. By contrast, Van Valen's Red Queen hypothesis is often put forward as the sole representative of the view that biotic forcing is the main evolutionary driver. This imbalance of hypotheses does not reflect our current knowledge: theoretical work demonstrates the plausibility of biotically driven long-term evolution, whereas empirical work suggests a central role for biotic forcing in macroevolution. We call for a more pluralistic view of how biotic forces may drive long-term evolution that is compatible with both phenotypic stasis in the fossil record and with non-constant extinction rates. Promising avenues of research include contrasting predictions from relevant theories within ecology and macroevolution, as well as embracing both abiotic and biotic proxies while modelling long-term evolutionary data. By fitting models describing hypotheses of biotically driven macroevolution to data, we could dissect their predictions and transcend beyond pattern description, possibly narrowing the divide between our current understanding of micro- and macroevolution. PMID:25948685

Advice networks in teams: the role of transformational leadership and members' core self-evaluations.

PubMed

Zhang, Zhen; Peterson, Suzanne J

2011-09-01

This article examines the team-level factors promoting advice exchange networks in teams. Drawing upon theory and research on transformational leadership, team diversity, and social networks, we hypothesized that transformational leadership positively influences advice network density in teams and that advice network density serves as a mediating mechanism linking transformational leadership to team performance. We further hypothesized a 3-way interaction in which members' mean core self-evaluation (CSE) and diversity in CSE jointly moderate the transformational leadership-advice network density relationship, such that the relationship is positive and stronger for teams with low diversity in CSE and high mean CSE. In addition, we expected that advice network centralization attenuates the positive influence of network density on team performance. Results based on multisource data from 79 business unit management teams showed support for these hypotheses. The results highlight the pivotal role played by transformational leadership and team members' CSEs in enhancing team social networks and, ultimately, team effectiveness. PsycINFO Database Record (c) 2011 APA, all rights reserved

Evaluating the role of admixture in cancer therapy via in vitro drug response and multivariate genome-wide associations

PubMed Central

Jack, John; Havener, Tammy M; McLeod, Howard L; Motsinger-Reif, Alison A; Foster, Matthew

2015-01-01

Aim: We investigate the role of ethnicity and admixture in drug response across a broad group of chemotherapeutic drugs. Also, we generate hypotheses on the genetic variants driving differential drug response through multivariate genome-wide association studies. Methods: Immortalized lymphoblastoid cell lines from 589 individuals (Hispanic or non-Hispanic/Caucasian) were used to investigate dose-response for 28 chemotherapeutic compounds. Univariate and multivariate statistical models were used to elucidate associations between genetic variants and differential drug response as well as the role of ethnicity in drug potency and efficacy. Results & Conclusion: For many drugs, the variability in drug response appears to correlate with self-reported race and estimates of genetic ancestry. Additionally, multivariate genome-wide association analyses offered interesting hypotheses governing these differential responses. PMID:26314407

Use of Hemadsorption in a Case of Pediatric Toxic Shock Syndrome.

PubMed

Berkes, Andrea; Szikszay, Edit; Kappelmayer, János; Kerényi, Adrienne; Szabó, Tamás; Ujhelyi, László; Bari, Krisztina; Balla, György; Balla, József

2017-01-01

Toxic shock syndrome is a potentially fatal toxin-mediated disease. The role of toxins in this clinical entity made us hypothesize that extracorporeal blood purification with CytoSorb® could play a beneficial role in the clinical management of toxic shock syndrome. This case report describes the successful treatment of toxic shock syndrome using a combination of renal replacement therapy and hemadsorption in a pediatric patient. A 5-year-old girl with Down's syndrome presented with an inflamed area surrounding an insect bite, signs of systemic inflammation, and multiple organ failure. As previous attempts of immune modulation therapy were unsuccessful, renal replacement therapy was supplemented by the cytokine absorber CytoSorb. Treatment using this combination was associated with a rapid and significant stabilization in the hemodynamic situation and a decrease in inflammatory mediators within hours after the initiation of therapy. The application of CytoSorb therapy was simple and safe. The use of extracorporeal blood purification with CytoSorb proved potentially beneficial by removing toxins and inflammatory mediators in this case and could therefore play a role in the clinical management of toxic shock syndrome. Whether CytoSorb has the potential to even positively influence mortality in patients with toxic shock syndrome still needs to be confirmed.

Use of Hemadsorption in a Case of Pediatric Toxic Shock Syndrome

PubMed Central

Berkes, Andrea; Szikszay, Edit; Kerényi, Adrienne; Szabó, Tamás; Ujhelyi, László; Bari, Krisztina; Balla, György

2017-01-01

Background Toxic shock syndrome is a potentially fatal toxin-mediated disease. The role of toxins in this clinical entity made us hypothesize that extracorporeal blood purification with CytoSorb® could play a beneficial role in the clinical management of toxic shock syndrome. This case report describes the successful treatment of toxic shock syndrome using a combination of renal replacement therapy and hemadsorption in a pediatric patient. Case Presentation A 5-year-old girl with Down's syndrome presented with an inflamed area surrounding an insect bite, signs of systemic inflammation, and multiple organ failure. As previous attempts of immune modulation therapy were unsuccessful, renal replacement therapy was supplemented by the cytokine absorber CytoSorb. Treatment using this combination was associated with a rapid and significant stabilization in the hemodynamic situation and a decrease in inflammatory mediators within hours after the initiation of therapy. The application of CytoSorb therapy was simple and safe. Conclusion The use of extracorporeal blood purification with CytoSorb proved potentially beneficial by removing toxins and inflammatory mediators in this case and could therefore play a role in the clinical management of toxic shock syndrome. Whether CytoSorb has the potential to even positively influence mortality in patients with toxic shock syndrome still needs to be confirmed. PMID:28791185

Transcranial magnetic stimulation to dorsolateral prefrontal cortex affects conflict-induced behavioural adaptation in a Wisconsin Card Sorting Test analogue.

PubMed

Boschin, Erica A; Mars, Rogier B; Buckley, Mark J

2017-01-08

A substantial body of literature has proposed a role for dorsolateral prefrontal cortex (dlPFC) in supporting behavioural adaptation during conflict tasks. The vast majority of the evidence in support of this interpretation comes from neuroimaging studies. However, in order to unequivocally ascribe such a role to dlPFC, it is important to determine whether or not it is essential for this mechanism, and this can only be achieved by lesioning the area or interfering with its activity. In this study, we investigated the effects of repeated Transcranial Magnetic Stimulation (rTMS) to dlPFC on performance on a conflict version of a Wisconsin Card Sorting Test analogue (used previously in circumscribed lesion studies in monkeys) in neurologically healthy human participants. Our results supported the view of dlPFC as a fundamental structure for optimal conflict-induced behavioural adaptation, as stimulation cancelled out the adaptation effect normally observed on control trials. We show that there is some indication of differential modulation of trial types by stimulation and we hypothesize that this might suggest a role for dlPFC in conflict-induced adaptation that is more specifically concerned with the maintenance of conflict-history information online across trials. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Critical Roles of the Direct GABAergic Pallido-cortical Pathway in Controlling Absence Seizures

PubMed Central

Li, Min; Ma, Tao; Wu, Shengdun; Ma, Jingling; Cui, Yan; Xia, Yang; Xu, Peng; Yao, Dezhong

2015-01-01

The basal ganglia (BG), serving as an intermediate bridge between the cerebral cortex and thalamus, are believed to play crucial roles in controlling absence seizure activities generated by the pathological corticothalamic system. Inspired by recent experiments, here we systematically investigate the contribution of a novel identified GABAergic pallido-cortical pathway, projecting from the globus pallidus externa (GPe) in the BG to the cerebral cortex, to the control of absence seizures. By computational modelling, we find that both increasing the activation of GPe neurons and enhancing the coupling strength of the inhibitory pallido-cortical pathway can suppress the bilaterally synchronous 2–4 Hz spike and wave discharges (SWDs) during absence seizures. Appropriate tuning of several GPe-related pathways may also trigger the SWD suppression, through modulating the activation level of GPe neurons. Furthermore, we show that the previously discovered bidirectional control of absence seizures due to the competition between other two BG output pathways also exists in our established model. Importantly, such bidirectional control is shaped by the coupling strength of this direct GABAergic pallido-cortical pathway. Our work suggests that the novel identified pallido-cortical pathway has a functional role in controlling absence seizures and the presented results might provide testable hypotheses for future experimental studies. PMID:26496656

Executive function depletion in children and its impact on theory of mind.

PubMed

Powell, Lindsey J; Carey, Susan

2017-07-01

The current studies provide an experimental, rather than correlational, method for testing hypotheses about the role of executive function (EF) in conceptual development. Previous research has established that adults' tendency to deploy EF can be temporarily diminished by use. Exercising self-control in one context decreases adults' performance on other EF demanding tasks immediately thereafter. Using two different depletion methods, Experiments 1 and 3 extend this finding to preschool-aged children. Experiments 2 and 4 make use of these EF depletion methods to elucidate the role of EF in children's theory of mind reasoning. Experiment 2 shows that EF depletion affects 5-year-olds' ability to predict another's behavior on the basis of that person's false belief, and Experiment 4 shows that this negative effect of depletion extends to 4- and 5-year-olds' ability to explain others' behavior on the basis of their false beliefs. These findings provide direct evidence that EF is required for the expression of an understanding of others' false beliefs across a variety of task demands, even in children who clearly have the capacity to construct such representations. We suggest ways in which depletion may be used as a tool for further investigating the role of executive function in cognitive development. Copyright © 2017. Published by Elsevier B.V.

Is Hand Selection Modulated by Cognitive-perceptual Load?

PubMed

Liang, Jiali; Wilkinson, Krista; Sainburg, Robert L

2018-01-15

Previous studies proposed that selecting which hand to use for a reaching task appears to be modulated by a factor described as "task difficulty". However, what features of a task might contribute to greater or lesser "difficulty" in the context of hand selection decisions has yet to be determined. There has been evidence that biomechanical and kinematic factors such as movement smoothness and work can predict patterns of selection across the workspace, suggesting a role of predictive cost analysis in hand-selection. We hypothesize that this type of prediction for hand-selection should recruit substantial cognitive resources and thus should be influenced by cognitive-perceptual loading. We test this hypothesis by assessing the role of cognitive-perceptual loading on hand selection decisions, using a visual search task that presents different levels of difficulty (cognitive-perceptual load), as established in previous studies on overall response time and efficiency of visual search. Although the data are necessarily preliminary due to small sample size, our data suggested an influence of cognitive-perceptual load on hand selection, such that the dominant hand was selected more frequently as cognitive load increased. Interestingly, cognitive-perceptual loading also increased cross-midline reaches with both hands. Because crossing midline is more costly in terms of kinematic and kinetic factors, our findings suggest that cognitive processes are normally engaged to avoid costly actions, and that the choice not-to-cross midline requires cognitive resources. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Viewer-centered and body-centered frames of reference in direct visuomotor transformations.

PubMed

Carrozzo, M; McIntyre, J; Zago, M; Lacquaniti, F

1999-11-01

It has been hypothesized that the end-point position of reaching may be specified in an egocentric frame of reference. In most previous studies, however, reaching was toward a memorized target, rather than an actual target. Thus, the role played by sensorimotor transformation could not be disassociated from the role played by storage in short-term memory. In the present study the direct process of sensorimotor transformation was investigated in reaching toward continuously visible targets that need not be stored in memory. A virtual reality system was used to present visual targets in different three-dimensional (3D) locations in two different tasks, one with visual feedback of the hand and arm position (Seen Hand) and the other without such feedback (Unseen Hand). In the Seen Hand task, the axes of maximum variability and of maximum contraction converge toward the mid-point between the eyes. In the Unseen Hand task only the maximum contraction correlates with the sight-line and the axes of maximum variability are not viewer-centered but rotate anti-clockwise around the body and the effector arm during the move from the right to the left workspace. The bulk of findings from these and previous experiments support the hypothesis of a two-stage process, with a gradual transformation from viewer-centered to body-centered and arm-centered coordinates. Retinal, extra-retinal and arm-related signals appear to be progressively combined in superior and inferior parietal areas, giving rise to egocentric representations of the end-point position of reaching.

Salivary oxytocin in adolescents with conduct problems and callous-unemotional traits.

PubMed

Levy, Tomer; Bloch, Yuval; Bar-Maisels, Meytal; Gat-Yablonski, Galia; Djalovski, Amir; Borodkin, Katy; Apter, Alan

2015-12-01

Callous-unemotional (CU) traits correlate with the severity and prognosis of conduct disorder in youth. The neuropeptide oxytocin (OT) has been linked to prosocial behaviors, including empathy and collaboration with others. This study discusses a possible role for OT in the biology of delinquent behavior. We hypothesized that in delinquent youth OT secretion will correlate with the severity of conduct problems and specifically with the level of CU traits. The study group included 67 male adolescents (mean age 16.2 years) undergoing residential treatment, previously assessed by an open clinical interview and history for the psychiatric diagnosis. Staff based Inventory of Callous-Unemotional traits for psychopathy and Strength and Difficulties Questionnaire were administered, and patients' medical and social personal files were systematically coded for previous history of antisocial acts using the Brown-Goodwin Questionnaire. Salivary OT was assayed by ELISA. Salivary OT levels were inversely correlated with conduct problems severity on Strength and Difficulties Questionnaire (r = -0.27; p ≤ 0.01). Recorded history of antisocial acts did not correlate with current OT levels. Odds ratio (OR) for significant CU traits among subjects with conduct problems was increased in low-OT (OR = 14, p ≤ 0.05) but not in high-OT subjects (OR = 6, p ≥ 0.05). Children with conduct problems and low levels of salivary OT are at risk for significant CU traits. These results suggest a possible role for salivary OT as a biomarker for CU traits and conduct problems severity.

Cysteine desulfurase IscS2 plays a role in oxygen resistance in Clostridium difficile.

PubMed

Giordano, Nicole; Hastie, Jessica L; Smith, Ashley D; Foss, Elissa D; Gutierrez-Munoz, Daniela F; Carlson, Paul E

2018-06-04

Clostridium difficile is an anaerobic, spore-forming bacterium capable of colonizing the gastrointestinal tract of humans following disruption of the normal microbiota, typically from antibiotic therapy for an unrelated infection. With approximately 500,000 confirmed infections leading to 29,000 deaths per year in the United States, C. difficile infection (CDI) is an urgent public health threat. We previously determined C. difficile survives in up to 3% oxygen. Low levels of oxygen are present in the intestinal tract with the higher concentrations being associated with the epithelial cell surface. Additionally, antibiotic treatment, the greatest risk factor for CDI, increases intestinal oxygen concentration. Therefore, we hypothesized that the C. difficile genome encodes mechanisms for survival during oxidative stress. Previous data have shown that cysteine desulfurases involved in iron-sulfur cluster assembly are involved in protecting bacteria from oxidative stress. In this study, deletion of a putative cysteine desulfurase ( Cd 630_12790/IscS2) involved in the iron sulfur cluster (Isc) system caused a severe growth defect in the presence of 2% oxygen. Additionally, this mutant delayed colonization in a conventional mouse model of CDI, and failed to colonize in a germ-free model, which has higher intestinal oxygen levels. These data imply an undefined role for this cysteine desulfurase in protecting C. difficile from low levels of oxygen in the gut. This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Conspecific and not performance-based attraction on immigrants drives colony growth in a waterbird.

PubMed

Tenan, Simone; Fasola, Mauro; Volponi, Stefano; Tavecchia, Giacomo

2017-09-01

Local recruitment and immigration play an important part in the dynamics and growth of animal populations. However, their estimation and incorporation into open population models is, in most cases, problematic. We studied factors affecting the growth of a recently established colony of Eurasian spoonbill (Platalea leucorodia) and assessed the contribution of local recruits, i.e. birds born in the colony, and immigrants, i.e. birds of unknown origin, to colony growth. We applied an integrated population model that accounts for uncertainty in breeding state assignment and merges population surveys, local fecundity and individual longitudinal data of breeding and non-breeding birds, to estimate demographic rates and the relative role of recruitment and immigration in driving the local dynamics. We also used this analytical framework to assess the degree of support for the 'performance-based' and 'conspecific attraction' hypotheses as possible mechanisms of colony growth. Among the demographic rates, only immigration was positively and significantly correlated with population growth rate. In addition, the number of immigrants settling in the colony was positively correlated with colony size in the previous and current year, but was not correlated with fecundity of the previous year. Our results suggest that the variation in immigration affected colony dynamics and that conspecific attraction likely triggered the relevant role of immigration in the growth of a recently formed waterbird colony, supporting the need of including immigration in population analysis. © 2017 The Authors. Journal of Animal Ecology © 2017 British Ecological Society.

Association between oxidative status and the composition of intestinal microbiota along the gastrointestinal tract.

PubMed

Gyuraszova, Marianna; Kovalcikova, Alexandra; Gardlik, Roman

2017-06-01

Studies have shown that the microbiota along the gastrointestinal tract (GIT) plays an important role when it comes to the maintenance of its proper functions. Many studies exist that have analyzed the composition of the bacterial community in the different regions of the GIT of humans and model animals. Microbial imbalance leads to several systemic disorders, including cardiovascular and renal disease. The imbalance between the production of reactive oxygen species (ROS) and their elimination by antioxidants leads to oxidative stress. Oxidative stress plays an important role in a variety of physiological processes, as well as disease. The continuous formation of ROS in the GIT is the result of the interaction between intestinal mucosa, symbiotic bacteria and dietary factors. It has also been proven that ROS play a role in the pathogenesis of several GI disorders, including IBD. We hypothesized that the levels of advanced glycation end products (AGEs) would be the highest in the ileum, caecum or colon, where the microbiota mostly consist of butyrate producing bacteria, Bacterioides, Clostridium, Ruminococcus or Bifidobacterium, which derive energy through carbohydrate fermentation. We also assumed that advanced oxidation protein products (AOPP) mostly act in the segments, where bacteria reside and which are responsible for the amino acid fermentation, such as caecum or colon. Lipid hydroxyperoxides are generated during digestion in the stomach, which contains absorbed oxygen and has a low pH. According to this we hypothesized that the highest concentration of thiobarbituric acid reacting substances (TBARS) could be in the stomach, which, however, has not been confirmed. Because Lactobacilli are able to produce catalase, an endogenous antioxidant, and are abundant in the small intestine, we hypothesized that antioxidant capacity (measured by ferric reducing ability) would be the highest here. The highest levels of AGEs were found in the caecum. The highest level of TBARS was found in the jejunum of the rats. The assessment of our hypothesis also revealed high levels of AOPP in the caecum. It has been shown that AOPP contributes to the progression of IBD. The ferric reducing ability of tissue was the lowest in the colon of the experimental animals, which is in accordance with previous studies that show that rat colon has a lower total antioxidant capacity than the small bowel. In summary, we offer some insight into the differences between the oxidative status along the GIT of rats and some advice concerning supportive antioxidant therapy of gastrointestinal diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

The Role of Insecure Attachment and Gender Role Stress in Predicting Controlling Behaviors in Men Who Batter

ERIC Educational Resources Information Center

Mahalik, James R.; Aldarondo, Etiony; Gilbert-Gokhale, Steven; Shore, Erika

2005-01-01

The authors hypothesized that masculine gender role stress would mediate the relationship between insecure attachment and controlling behaviors in a sample of men who batter. To examine this hypothesis, 143 men who were court mandated to attend a batterers' intervention program in a northeastern state completed measures including the Controlling…

The Referee Role and Norms of Equity: A Contribution Toward a Theory of Sibling Conflict

ERIC Educational Resources Information Center

Ihinger, Marilyn

1975-01-01

A theory relates amount of conflict in the sibling relationship to norms of distributive justice, or equity, within the family. The theory is limited to the parental referee role, and the consistency and congruity with which this role is enacted is hypothesized to directly influence the degree of sibling conflict. (Author)

Rolefulness: Social and Internal Sense of Role Satisfaction

ERIC Educational Resources Information Center

Kato, Daiki; Suzuki, Mikie

2018-01-01

The main purpose of this study is to hypothesize the existence of the general sense of role satisfaction and device a scale to measure it. The participants in study 1 were 1029 Japanese high school students (484 men and 545 women). The result of exploratory factor analysis suggested that the two-factor structure is adequate. One is "social…

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)

Tacit knowledge: A refinement and empirical test of the Academic Tacit Knowledge Scale.

PubMed

Insch, Gary S; McIntyre, Nancy; Dawley, David

2008-11-01

Researchers have linked tacit knowledge to improved organizational performance, but research on how to measure tacit knowledge is scarce. In the present study, the authors proposed and empirically tested a model of tacit knowledge and an accompanying measurement scale of academic tacit knowledge. They present 6 hypotheses that support the proposed tacit knowledge model regarding the role of cognitive (self-motivation, self-organization); technical (individual task, institutional task); and social (task-related, general) skills. The authors tested these hypotheses with 542 responses to the Academic Tacit Knowledge Scale, which included the respondents' grade point average-the performance variable. All 6 hypotheses were supported.

How to never be wrong.

PubMed

Gershman, Samuel J

2018-05-24

Human beliefs have remarkable robustness in the face of disconfirmation. This robustness is often explained as the product of heuristics or motivated reasoning. However, robustness can also arise from purely rational principles when the reasoner has recourse to ad hoc auxiliary hypotheses. Auxiliary hypotheses primarily function as the linking assumptions connecting different beliefs to one another and to observational data, but they can also function as a "protective belt" that explains away disconfirmation by absorbing some of the blame. The present article traces the role of auxiliary hypotheses from philosophy of science to Bayesian models of cognition and a host of behavioral phenomena, demonstrating their wide-ranging implications.

Intelligence, previous convictions and interrogative suggestibility: a path analysis of alleged false-confession cases.

PubMed

Sharrock, R; Gudjonsson, G H

1993-05-01

The main purpose of this study was to investigate the relationship between interrogative suggestibility and previous convictions among 108 defendants in criminal trials, using a path analysis technique. It was hypothesized that previous convictions, which may provide defendants with interrogative experiences, would correlate negatively with 'shift' as measured by the Gudjonsson Suggestibility Scale (Gudjonsson, 1984a), after intelligence and memory had been controlled for. The hypothesis was partially confirmed and the theoretical and practical implications of the findings are discussed.

Science from evaluation: testing hypotheses about differential effects of three youth-focused suicide prevention trainings.

PubMed

Coleman, Daniel; Del Quest, Aisling

2015-01-01

As part of an evaluation component of a youth suicide prevention, a quasi-experimental repeated measures design tested hypotheses about two brief suicide prevention gatekeeper trainings (Question, Persuade, Refer [QPR] and RESPONSE) and one longer suicide intervention skills training (Applied Suicide Intervention Skills Training [ASIST]). All three trainings showed large changes in prevention attitudes and self-efficacy, largely maintained at follow-up. ASIST trainees had large increases in asking at-risk youth about suicide at follow-up. Convergent with other research, modeling and role-play in training are crucial to increased prevention behaviors. Practice and research implications are discussed, including social work roles in suicide prevention and research.

Exhumation of the Black Mountains in Death Valley, California, with new thermochronometric data from the Badwater Turtleback

NASA Astrophysics Data System (ADS)

Sizemore, T. M.; Cemen, I.; Wielicki, M. M.; Stockli, D. F.; Heizler, M. T.; Lutz, B. M.

2017-12-01

The Black Mountains, in Death Valley, California, are one of the key areas to better understand Basin and Range extension because they contain Cenozoic igneous and sedimentary rocks overlying mid- to deep-crustal, 1.74 Ga basement gneiss with abundant fault striations, large-scale extensional folds, and tectonite fabrics containing top-to-the-northwest shear-sense indicators. These rocks make up the footwall of three prominent, high-relief "turtleback" fault surfaces in the western flank of the Black Mountains, which are thought to have accommodated a significant amount of strain in the Death Valley area. It is unknown whether the missing Paleozoic and Mesozoic strata in the Black Mountains were removed in association with high-angle faulting, or along a continuous detachment surface with a rolling-hinge style of faulting as the hanging wall moved to the west, now forming the Panamint Range. The turtlebacks play an important role in resolving this question because they are commonly cited as containing conflicting evidence of both hypotheses. To provide insight into this problem, we are building an exhumation model across the Black Mountains using previously published thermochronometric data as well as new transect-based (U-Th)/He and Ar-Ar thermochronology and U-Pb geochronology for the Badwater turtleback. The model will provide a four-dimensional view of the exhumation history of the Black Mountains, to serve as evidence for either of the two previously mentioned hypotheses, or possibly some other style of exhumation. Additionally, we will compare the exhumation history of the Black Mountains to that of the Panamint Range using previously published data and interpretations. Our preliminary zircon U-Pb data suggest a crystallization age for the gneissic rocks on the Badwater turtleback of 1.74 Ga (207Pb/206Pb, 2σ error=31.8 Ma, n=6) with two younger populations at 1.46 Ga (207Pb/206Pb, 2σ error=51.8 Ma, n=3) and 79.6 Ma (206Pb/238U, 2σ error=10.0 Ma, n=2), possibly reflecting post-crystallization alteration. This is in agreement with previously published ages. The zircon 206Pb/238U ages of the Smith Mountain Granite, exposed at the top of the Badwater turtleback, range from 3.06-9.71 Ma (n=11), confirming Cenozoic intrusion of the pluton.

The role of methionine metabolism in inflammatory bowel disease

USDA-ARS?s Scientific Manuscript database

Methionine (Met) cycle activity is critical for normal cell functions. Met metabolites S-adenosylmethionine (SAM) and methylthioadenosine (MTA) are anti-inflammatory, yet their role in inflammatory bowel disease (IBD) is poorly understood. We hypothesize that active IBD leads to changes in Met metab...

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.

Culture, Cross-Role Consistency, and Adjustment: Testing Trait and Cultural Psychology Perspectives

PubMed Central

Church, A. Timothy; Anderson-Harumi, Cheryl A.; del Prado, Alicia M.; Curtis, Guy J.; Tanaka-Matsumi, Junko; Valdez Medina, José L.; Mastor, Khairul A.; White, Fiona A.; Miramontes, Lilia A.; Katigbak, Marcia S.

2008-01-01

Trait and cultural psychology perspectives on cross-role consistency and its relation to adjustment were examined in two individualistic cultures, the United States (N = 231) and Australia (N = 195), and four collectivistic cultures, Mexico (N = 199), Philippines (N = 195), Malaysia (N = 217), and Japan (N = 180). Cross-role consistency in trait ratings was evident in all cultures, supporting trait perspectives. Cultural comparisons of mean consistency provided support for cultural psychology perspectives as applied to East Asian cultures (i.e., Japan), but not collectivistic cultures more generally. Some but not all of the hypothesized predictors of consistency were supported across cultures. Cross-role consistency predicted aspects of adjustment in all cultures, but prediction was most reliable in the American sample and weakest in the Japanese sample. Alternative constructs proposed by cultural psychologists—personality coherence, social appraisal, and relationship harmony—predicted adjustment in all cultures, but were not, as hypothesized, better predictors of adjustment in collectivistic cultures than in individualistic cultures. PMID:18729706

Culture, cross-role consistency, and adjustment: testing trait and cultural psychology perspectives.

PubMed

Church, A Timothy; Anderson-Harumi, Cheryl A; del Prado, Alicia M; Curtis, Guy J; Tanaka-Matsumi, Junko; Valdez Medina, José L; Mastor, Khairul A; White, Fiona A; Miramontes, Lilia A; Katigbak, Marcia S

2008-09-01

Trait and cultural psychology perspectives on cross-role consistency and its relation to adjustment were examined in 2 individualistic cultures, the United States (N=231) and Australia (N=195), and 4 collectivistic cultures, Mexico (N=199), the Philippines (N=195), Malaysia (N=217), and Japan (N=180). Cross-role consistency in trait ratings was evident in all cultures, supporting trait perspectives. Cultural comparisons of mean consistency provided support for cultural psychology perspectives as applied to East Asian cultures (i.e., Japan) but not collectivistic cultures more generally. Some but not all of the hypothesized predictors of consistency were supported across cultures. Cross-role consistency predicted aspects of adjustment in all cultures, but prediction was most reliable in the U.S. sample and weakest in the Japanese sample. Alternative constructs proposed by cultural psychologists--personality coherence, social appraisal, and relationship harmony--predicted adjustment in all cultures but were not, as hypothesized, better predictors of adjustment in collectivistic cultures than in individualistic cultures.

Population dynamics of Lutzomyia shannoni (Diptera: Psychodidae) in relation to the epizootiology of vesicular stomatitis virus on Ossabaw Island, Georgia.

PubMed

Comer, J A; Kavanaugh, D M; Stallknecht, D E; Corn, J L

1994-11-01

Population dynamics of Lutzomyia shannoni Dyar were studied on Ossabaw Island, GA, to define further the role of this species in the epizootiology of the New Jersey serotype of vesicular stomatitis (VSNJ) virus. Bimonthly collections of sand flies egressing from hollow trees from April to November 1991 indicated that there were three generations of sand flies. Data from light trap collections from 1986 through 1989 indicated that similar seasonal cycles occurred during previous years. At this site, we hypothesize that L. shannoni undergoes facultative diapause. Two isolates of VSNJ virus were obtained from female sand flies collected in May and June of 1991. We believe that the virus overwinters in immature L. shannoni and that transovarially infected sand flies emerging each spring initiate a summer amplification cycle in swine on Ossabaw Island.

The origin of Behçet's disease geoepidemiology: possible role of a dual microbial-driven genetic selection.

PubMed

Piga, Matteo; Mathieu, Alessandro

2014-01-01

It is recognised that the genetic profiles that give rise to chronic inflammatory diseases, under the influence of environmental agents, might have been implicated in the host defence mechanism against lethal infections in the past. Behçet's disease (BD) is an immune-mediated inflammatory disease, expressed as vasculitis, triggered by environmental factors in genetically susceptible individuals. We carried out a review of published data to draw up an evolutionary adaptation model, as Author's perspective, for genetic susceptibility factors and inflammatory immune response involved in BD pathogenesis. Two lethal infectious agents, Plasmodium Falciparum and Yersinia Pestis, are proposed as the putative driving forces that favoured the fixing of the major genetic susceptibility factors to BD, thus determining its geoepidemiology. Further studies are needed to confirm the validity of this evolutionary model which includes and integrates the key insights of previous hypotheses.

Carnivore activity in the Sima de los Huesos (Atapuerca, Spain) hominin sample

NASA Astrophysics Data System (ADS)

Sala, Nohemi; Arsuaga, Juan Luis; Martínez, Ignacio; Gracia-Téllez, Ana

2014-08-01

The Sima de los Huesos (SH) site is the largest accumulation of human remains from the Middle Pleistocene known to date. Studies in the last two decades have proposed different hypotheses to explain carnivore activity in the SH human sample. This study provides new data in order to test these different interpretations, and therefore to understand the role of the carnivores in site formation at SH. Carnivores are usually not the origin of large accumulations of hominin fossils in the Eurasian record. The results show that marks of carnivore activity in the SH sample appear very infrequently, which we interpret as indicating that carnivore activity was very sporadic at the site. This is in stark contrast with previous studies. The comparison of bone modification patterns at SH to actualistic carnivore data allows us to suggest that bears were likely to have been the carnivore responsible for the modification observed on both human and bear fossils.

Numeracy moderates the influence of task-irrelevant affect on probability weighting.

PubMed

Traczyk, Jakub; Fulawka, Kamil

2016-06-01

Statistical numeracy, defined as the ability to understand and process statistical and probability information, plays a significant role in superior decision making. However, recent research has demonstrated that statistical numeracy goes beyond simple comprehension of numbers and mathematical operations. On the contrary to previous studies that were focused on emotions integral to risky prospects, we hypothesized that highly numerate individuals would exhibit more linear probability weighting because they would be less biased by incidental and decision-irrelevant affect. Participants were instructed to make a series of insurance decisions preceded by negative (i.e., fear-inducing) or neutral stimuli. We found that incidental negative affect increased the curvature of the probability weighting function (PWF). Interestingly, this effect was significant only for less numerate individuals, while probability weighting in more numerate people was not altered by decision-irrelevant affect. We propose two candidate mechanisms for the observed effect. Copyright © 2016 Elsevier B.V. All rights reserved.

MreB: pilot or passenger of cell wall synthesis?

PubMed

White, Courtney L; Gober, James W

2012-02-01

The discovery that the bacterial cell shape determinant MreB is related to actin spurred new insights into bacterial morphogenesis and development. The trafficking and mechanical roles of the eukaryotic cytoskeleton were hypothesized to have a functional ancestor in MreB based on evidence implicating MreB as an organizer of cell wall synthesis. Genetic, biochemical and cytological studies implicate MreB as a coordinator of a large multi-protein peptidoglycan (PG) synthesizing holoenzyme. Recent advances in microscopy and new biochemical evidence, however, suggest that MreB may function differently than previously envisioned. This review summarizes our evolving knowledge of MreB and attempts to refine the generalized model of the proteins organizing PG synthesis in bacteria. This is generally thought to be conserved among eubacteria and the majority of the discussion will focus on studies from a few well-studied model organisms. Copyright © 2011 Elsevier Ltd. All rights reserved.

Computation of linear acceleration through an internal model in the macaque cerebellum

PubMed Central

Laurens, Jean; Meng, Hui; Angelaki, Dora E.

2013-01-01

A combination of theory and behavioral findings has supported a role for internal models in the resolution of sensory ambiguities and sensorimotor processing. Although the cerebellum has been proposed as a candidate for implementation of internal models, concrete evidence from neural responses is lacking. Here we exploit un-natural motion stimuli, which induce incorrect self-motion perception and eye movements, to explore the neural correlates of an internal model proposed to compensate for Einstein’s equivalence principle and generate neural estimates of linear acceleration and gravity. We show that caudal cerebellar vermis Purkinje cells and cerebellar nuclei neurons selective for actual linear acceleration also encode erroneous linear acceleration, as expected from the internal model hypothesis, even when no actual linear acceleration occurs. These findings provide strong evidence that the cerebellum might be involved in the implementation of internal models that mimic physical principles to interpret sensory signals, as previously hypothesized by theorists. PMID:24077562

Cryptic vicariance in the historical assembly of a Baja California peninsular desert biota.

PubMed

Riddle, B R; Hafner, D J; Alexander, L F; Jaeger, J R

2000-12-19

We use analyses of phylogeographic population structure across a suite of 12 mammalian, avian, amphibian, and reptilian species and species-groups to assess the role of Late Miocene to Pleistocene geological history in the evolution of a distinct Baja California Peninsular Desert biota. Comparative examination of phylogroup distributions provides support for previously hypothesized vicariant events produced by: a middle Pleistocene midpeninsular seaway, a late Pliocene northward transgression of the Sea of Cortéz, and a Pliocene seaway across the southern peninsular Isthmus of La Paz. Most of this phylogeographic architecture is cryptically embedded within widespread taxonomic species and species-groups, such that the unique evolutionary history of the Peninsular Desert has been obscured and ignored. The Peninsular Desert can no longer be considered a subset of the Sonoran Desert-it is a separate regional desert with its own unique evolutionary history, ecological arena, and conservation value.

Parents of adolescents with psychiatric disorders: insight into the disorder, self-stigma and parental stress.

PubMed

Hasson-Ohayon, Ilanit; Tuval-Mashiach, Rivka; Morag-Yaffe, Mayad; Gaziel, Meyrav; Schapir, Lior; Zalsman, Gil; Shoval, Gal

2014-07-01

Parents of adolescents with mental disorders experience stress partially due to the way they perceive and experience their offspring's disorder. The current study assessed the mediator role of self-stigma in the relationship between insight into the disorder and parental stress of parents of adolescents with mental disorders. A total of 37 parents of adolescents with psychiatric disorders were assessed for their level of insight, self-stigma and parental stress. The hypothesized mediation model was confirmed and is consistent with previous study on parents of adults with severe mental illness. The positive association between insight and parental stress is mediated by these parents' self-stigma, suggesting that insight increases the self-stigma, which in turn increases the parental stress. These results may have clinical implications with regard to the treatment of the family of adolescents with mental disorders. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Femtosecond-laser hyperdoping silicon in an SF{sub 6} atmosphere: Dopant incorporation mechanism

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

Sher, Meng-Ju, E-mail: msher@stanford.edu; Mangan, Niall M.; Lin, Yu-Ting

2015-03-28

In this paper, we examine the fundamental processes that occur during femtosecond-laser hyperdoping of silicon with a gas-phase dopant precursor. We probe the dopant concentration profile as a function of the number of laser pulses and pressure of the dopant precursor (sulfur hexafluoride). In contrast to previous studies, we show the hyperdoped layer is single crystalline. From the dose dependence on pressure, we conclude that surface adsorbed molecules are the dominant source of the dopant atoms. Using numerical simulation, we estimate the change in flux with increasing number of laser pulses to fit the concentration profiles. We hypothesize that themore » native oxide plays an important role in setting the surface boundary condition. As a result of the removal of the native oxide by successive laser pulses, dopant incorporation is more efficient during the later stage of laser irradiation.« less

Population Vulnerability to Biannual Cholera Outbreaks and Associated Macro-Scale Drivers in the Bengal Delta

PubMed Central

Akanda, Ali Shafqat; Jutla, Antarpreet S.; Gute, David M.; Sack, R. Bradley; Alam, Munirul; Huq, Anwar; Colwell, Rita R.; Islam, Shafiqul

2013-01-01

The highly populated floodplains of the Bengal Delta have a long history of endemic and epidemic cholera outbreaks, both coastal and inland. Previous studies have not addressed the spatio-temporal dynamics of population vulnerability related to the influence of underlying large-scale processes. We analyzed spatial and temporal variability of cholera incidence across six surveillance sites in the Bengal Delta and their association with regional hydroclimatic and environmental drivers. More specifically, we use salinity and flood inundation modeling across the vulnerable districts of Bangladesh to test earlier proposed hypotheses on the role of these environmental variables. Our results show strong influence of seasonal and interannual variability in estuarine salinity on spring outbreaks and inland flooding on fall outbreaks. A large segment of the population in the Bengal Delta floodplains remain vulnerable to these biannual cholera transmission mechanisms that provide ecologic and environmental conditions for outbreaks over large geographic regions. PMID:24019441

Hormones and ethics: Understanding the biological basis of unethical conduct.

PubMed

Lee, Jooa Julia; Gino, Francesca; Jin, Ellie Shuo; Rice, Leslie K; Josephs, Robert A

2015-10-01

Globally, fraud has been rising sharply over the last decade, with current estimates placing financial losses at greater than $3.7 trillion annually. Unfortunately, fraud prevention has been stymied by lack of a clear and comprehensive understanding of its underlying causes and mechanisms. In this paper, we focus on an important but neglected topic--the biological antecedents and consequences of unethical conduct--using salivary collection of hormones (testosterone and cortisol). We hypothesized that preperformance cortisol levels would interact with preperformance levels of testosterone to regulate cheating behavior in 2 studies. Further, based on the previously untested cheating-as-stress-reduction hypothesis, we predicted a dose-response relationship between cheating and reductions in cortisol and negative affect. Taken together, this research marks the first foray into the possibility that endocrine-system activity plays an important role in the regulation of unethical behavior. (c) 2015 APA, all rights reserved).

Abyssal Upwelling in Mid-Ocean Ridge Fracture Zones

NASA Astrophysics Data System (ADS)

Clément, Louis; Thurnherr, Andreas M.

2018-03-01

Turbulence in the abyssal ocean plays a fundamental role in the climate system by sustaining the deepest branch of the overturning circulation. Over the western flank of the Mid-Atlantic Ridge in the South Atlantic, previously observed bottom-intensified and tidally modulated mixing of abyssal waters appears to imply a counterintuitive densification of deep and bottom waters. Here we show that inside fracture zones, however, turbulence is elevated away from the seafloor because of intensified downward propagating near-inertial wave energy, which decays below a subinertial shear maximum. Ray-tracing simulations predict a decay of wave energy subsequent to wave-mean flow interactions. The hypothesized wave-mean flow interactions drive a deep flow toward lighter densities of up to 0.6 Sv over the mid-ocean ridge flank in the Brazil Basin, and the same process may also cause upwelling of abyssal waters in other ocean basins with mid-ocean ridges with fracture zones.

Remarriage of women and men after divorce: the role of socioeconomic prospects.

PubMed

Sweeney, M M

1997-09-01

"This analysis of remarriage among the Wisconsin Longitudinal Study's cohort of high school graduates investigates the relationship between socioeconomic prospects and remarriage after divorce. This article expands on previous efforts by including multiple measures of socioeconomic prospects and considering their importance over an extended time frame. In addition, a comparative approach is taken in this analysis, with the importance of socioeconomic prospects considered for the remarriage of both women and men. Several competing hypotheses are tested, with results indicating that, for women, the appropriate model of remarriage varies with age of separation from the first husband. With few exceptions, socioeconomic prospects are not found to be related to the remarriage of men. The implications of these findings for patterns of poverty among divorced women are considered." This paper was originally presented at the 1995 Annual Meeting of the Population Association of America. excerpt

Theoretical investigation of the gas-phase reactions of CrO(+) with ethylene.

PubMed

Scupp, Thomas M; Dudley, Timothy J

2010-01-21

The potential energy surfaces associated with the reactions of chromium oxide cation (CrO(+)) with ethylene have been characterized using density functional, coupled-cluster, and multireference methods. Our calculations show that the most probable reaction involves the formation of acetaldehyde and Cr(+) via a hydride transfer involving the metal center. Our calculations support previous experimental hypotheses that a four-membered ring intermediate plays an important role in the reactivity of the system. We have also characterized a number of viable reaction pathways that lead to other products, including ethylene oxide. Due to the experimental observation that CrO(+) can activate carbon-carbon bonds, a reaction pathway involving C-C bond cleavage has also been characterized. Since many of the reactions involve a change in the spin state in going from reactants to products, locations of these spin surface crossings are presented and discussed. The applicability of methods based on Hartree-Fock orbitals is also 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.

Frost hardiness of tree species is independent of phenology and macroclimatic niche.

PubMed

Hofmann, M; Bruelheide, H

2015-03-01

The differences in timing in bud burst between species have been interpreted as an adaptation to late frost events in spring. Thus, it has been suggested that the degree of frost susceptibility of leaves is species-specific and depends on the species' phenology and geographic distribution range. To test for relationships between frost tolerance and phenology as well as between frost tolerance and distribution range across Central European tree species, we studied the frost hardiness of closed buds before bud burst and of freshly opened buds at the time of bud burst. We hypothesized that species with early bud burst and species distributed in eastern and northern areas were more frost tolerant than species with late bud burst and species distributed in western and southern areas. Frost hardiness was estimated by exposing twigs to 11 frost temperatures between -4 °C and -80 °C and by assessing tissue damage by the electrolyte leakage method. In contrast to our hypotheses, neither frost hardiness of closed buds nor frost hardiness of freshly opened buds were related to any variable describing species' macroclimatic niche. Furthermore, frost hardiness of freshly opened buds did not differ among species. Thus, the investigated species with early bud burst take higher risks of frost damage than the species with late bud bursts. These findings indicate that frost hardiness might not play the key role in limiting the geographic distribution ranges previously anticipated.

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

Changes in protein expression during honey bee larval development.

PubMed

Chan, Queenie W T; Foster, Leonard J

2008-10-29

The honey bee (Apis mellifera), besides its role in pollination and honey production, serves as a model for studying the biochemistry of development, metabolism, and immunity in a social organism. Here we use mass spectrometry-based quantitative proteomics to quantify nearly 800 proteins during the 5- to 6-day larval developmental stage, tracking their expression profiles. We report that honey bee larval growth is marked by an age-correlated increase of protein transporters and receptors, as well as protein nutrient stores, while opposite trends in protein translation activity and turnover were observed. Levels of the immunity factors prophenoloxidase and apismin are positively correlated with development, while others surprisingly were not significantly age-regulated, suggesting a molecular explanation for why bees are susceptible to major age-associated bee bacterial infections such as American Foulbrood or fungal diseases such as chalkbrood. Previously unreported findings include the reduction of antioxidant and G proteins in aging larvae. These data have allowed us to integrate disparate findings in previous studies to build a model of metabolism and maturity of the immune system during larval development. This publicly accessible resource for protein expression trends will help generate new hypotheses in the increasingly important field of honey bee research.

A Combination of Soybean and Haematococcus Extract Alleviates Ultraviolet B-Induced Photoaging

PubMed Central

Shin, Jieun; Kim, Jong-Eun; Pak, Kum-Ju; Kang, Jung Il; Kim, Tae-Seok; Lee, Sang-Yoon; Yeo, Ik-Hyun; Park, Jung Han Yoon; Kim, Jong Hun; Kang, Nam Joo; Lee, Ki Won

2017-01-01

Soybean-derived isoflavones have been investigated for their preventative effects against UV-induced symptoms of skin damage including wrinkle formation and inflammation. Haematococcus pluvialis is a freshwater species of Chlorophyta that contains high concentrations of the natural carotenoid pigment astaxanthin. Astaxanthin is known to be involved in retinoic acid receptor (RAR) signaling and previously been associated with the inhibition of activator protein (AP)-1 dependent transcription. Based on previous studies, we hypothesized that a combination of soy extract (SE) and Haematococcus extract (HE) may prevent UVB-induced photoaging through specific signaling pathways, as measured by UVB-induced wrinkling on hairless mice skin and expression changes in human dermal fibroblasts (HDFs). The 1:2 ratio of SE and HE mixture (SHM) showed the optimal benefit in vivo. SHM was found to inhibit wrinkle formation via the downregulation of matrix metalloproteinase (MMP)-1 mRNA and protein expression. SHM also inhibited mitogen-activated protein kinase (MAPK) phosphorylation and the transactivation of AP-1 which plays an important role in regulating MMP expression. These results highlight the potential for SHM to be developed as a therapeutic agent to prevent UVB-induced skin wrinkling. PMID:28327532

A Combination of Soybean and Haematococcus Extract Alleviates Ultraviolet B-Induced Photoaging.

PubMed

Shin, Jieun; Kim, Jong-Eun; Pak, Kum-Ju; Kang, Jung Il; Kim, Tae-Seok; Lee, Sang-Yoon; Yeo, Ik-Hyun; Park, Jung Han Yoon; Kim, Jong Hun; Kang, Nam Joo; Lee, Ki Won

2017-03-22

Soybean-derived isoflavones have been investigated for their preventative effects against UV-induced symptoms of skin damage including wrinkle formation and inflammation. Haematococcus pluvialis is a freshwater species of Chlorophyta that contains high concentrations of the natural carotenoid pigment astaxanthin. Astaxanthin is known to be involved in retinoic acid receptor (RAR) signaling and previously been associated with the inhibition of activator protein (AP)-1 dependent transcription. Based on previous studies, we hypothesized that a combination of soy extract (SE) and Haematococcus extract (HE) may prevent UVB-induced photoaging through specific signaling pathways, as measured by UVB-induced wrinkling on hairless mice skin and expression changes in human dermal fibroblasts (HDFs). The 1:2 ratio of SE and HE mixture (SHM) showed the optimal benefit in vivo. SHM was found to inhibit wrinkle formation via the downregulation of matrix metalloproteinase (MMP)-1 mRNA and protein expression. SHM also inhibited mitogen-activated protein kinase (MAPK) phosphorylation and the transactivation of AP-1 which plays an important role in regulating MMP expression. These results highlight the potential for SHM to be developed as a therapeutic agent to prevent UVB-induced skin wrinkling.

Epithelial-mesenchymal transition spectrum quantification and its efficacy in deciphering survival and drug responses of cancer patients.

PubMed

Tan, Tuan Zea; Miow, Qing Hao; Miki, Yoshio; Noda, Tetsuo; Mori, Seiichi; Huang, Ruby Yun-Ju; Thiery, Jean Paul

2014-10-01

Epithelial-mesenchymal transition (EMT) is a reversible and dynamic process hypothesized to be co-opted by carcinoma during invasion and metastasis. Yet, there is still no quantitative measure to assess the interplay between EMT and cancer progression. Here, we derived a method for universal EMT scoring from cancer-specific transcriptomic EMT signatures of ovarian, breast, bladder, lung, colorectal and gastric cancers. We show that EMT scoring exhibits good correlation with previously published, cancer-specific EMT signatures. This universal and quantitative EMT scoring was used to establish an EMT spectrum across various cancers, with good correlation noted between cell lines and tumours. We show correlations between EMT and poorer disease-free survival in ovarian and colorectal, but not breast, carcinomas, despite previous notions. Importantly, we found distinct responses between epithelial- and mesenchymal-like ovarian cancers to therapeutic regimes administered with or without paclitaxel in vivo and demonstrated that mesenchymal-like tumours do not always show resistance to chemotherapy. EMT scoring is thus a promising, versatile tool for the objective and systematic investigation of EMT roles and dynamics in cancer progression, treatment response and survival. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

The protective role of self-efficacy against workplace incivility and burnout in nursing: A time-lagged study.

PubMed

Fida, Roberta; Laschinger, Heather K Spence; Leiter, Michael P

Incivility has negative consequences in the workplace and remains a prevalent issue in nursing. Research has consistently linked incivility to nurse burnout and, in turn, to poor mental health and turnover intentions. To retain high-quality nurses, it is important to understand what factors might protect nurses from the negative effects of workplace mistreatment. The aim of the study was to investigate the role of relational occupational coping self-efficacy in protecting nurses from workplace incivility and related burnout and turnover intentions. A two-wave national sample of 596 Canadian nurses completed mail surveys both at Time 1 and one year later at Time 2. Structural equation modeling was used to test the hypothesized model. The model showed a good fit, and most of the hypothesized paths were significant. Overall, the results supported the hypothesized protective effect of relational occupational coping self-efficacy against incivility and later burnout, mental health, and turnover intentions. Relational occupational coping self-efficacy is an important protective factor against negative work behavior. Organizations should provide nurses with opportunities to build their coping strategies for managing job demands and difficult interpersonal interactions. Similarly, providing exposure to effective role models and providing meaningful verbal encouragement are other sources of efficacy information for building nurses' relational coping self-efficacy.

Animal testing is still the best way to find new treatments for patients.

PubMed

Garattini, Silvio; Grignaschi, Giuliano

2017-04-01

Experimental research proceeds by hypotheses formulated on the basis of previous or new knowledge and then tested. If they are accepted, they serve as the basis for further hypotheses, and if they are rejected new hypotheses can be developed. In other words, when we are at the frontiers of knowledge the path is forged by "trial and error". When a trial shows a hypothesis is wrong, this is a step toward making fewer errors. This process also applies to drug development. There is no magic formula at present to predict - at the pre-clinical level - the therapeutic value of a drug for people with a disease. However, pre-clinical studies are needed in order to formulate hypotheses that justify clinical trials. Without these preliminary studies in vitro and in vivo in selected animal species it would be unethical to test still unproven chemicals in humans. Copyright © 2016 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Mapping the areas sensitive to long-term endotoxin tolerance in the rat brain: a c-fos mRNA study.

PubMed

Vallès, Astrid; Martí, Octavi; Armario, Antonio

2005-06-01

We have recently found that a single endotoxin administration to rats reduced the hypothalamic-pituitary-adrenal response to another endotoxin administration 4 weeks later, which may be an example of the well-known phenomenon of endotoxin tolerance. However, the time elapsed between the two doses of endotoxin was long enough to consider the above results as an example of late tolerance, whose mechanisms are poorly characterized. To know if the brain plays a role in this phenomenon and to characterize the putative areas involved, we compared the c-fos mRNA response after a final dose of endotoxin in animals given vehicle or endotoxin 4 weeks before. Endotoxin caused a widespread induction of c-fos mRNA in the brain, similar to that previously reported by other laboratories. Whereas most of the brain areas were not sensitive to the previous experience with endotoxin, a few showed a reduced response in endotoxin-pretreated rats: the parvocellular and magnocellular regions of the paraventricular hypothalamic nucleus, the central amygdala, the lateral division of the bed nucleus and the locus coeruleus. We hypothesize that late tolerance to endotoxin may involve plastic changes in the brain, likely to be located in the central amygdala. The reduced activation of the central amygdala in rats previously treated with endotoxin may, in turn, reduce the activation of other brain areas, including the hypothalamic paraventicular nucleus.

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.

The Process of Mentoring Pregnant Adolescents: An Exploratory Study.

ERIC Educational Resources Information Center

Blinn-Pike, Lynn; Kuschel, Diane; McDaniel, Annette; Mingus, Suzanne; Mutti, Megan Poole

1998-01-01

The process that occurs in relationships between volunteer adult mentors and pregnant adolescent "mentees" is described empirically; testable hypotheses based on findings concerning the mentor role are proposed. Case records from 20 mentors are analyzed; findings regarding mentors' roles are discussed. Criteria for conceptualizing quasi-parenting…

The intrinsic circadian clock within the cardiomyocyte directly regulates myocardial gene expression, metabolism, and contractile function

USDA-ARS?s Scientific Manuscript database

Virtually every mammalian cell, including cardiomyocytes, possesses an intrinsic circadian clock. The role of this transcriptionally based molecular mechanism in cardiovascular biology remains unknown. We hypothesized that circadian clock within the cardiomyocyte plays a role in regulating myocardia...

The intrinsic circadian clock within the cardiomyocyte directly regulates myocardial gene expression, metabolism, and contractile function

USDA-ARS?s Scientific Manuscript database

Virtually every mammalian cell, including cardiomyocytes, possesses an intrinsic circadian clock. The role of this transcriptionally based molecular mechanism in cardiovascular biology remains unknown. We hypothesized that the circadian clock within the cardiomyocyte plays a role in regulating myo...

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.

The omega-3 fatty acid DHA dose-dependently reduces atherosclerosis: a putative role for F4-neuroprostanes a specific class of peroxidized metabolites

USDA-ARS?s Scientific Manuscript database

Objective. Consumption of long chain omega-3 polyunsaturated fatty acids is associated with reduced risks of cardiovascular disease but the role of their oxygenated metabolites remains unclear. We hypothesized that peroxidized metabolites of docosahexaenoic acid (DHA, 22:6 n-3) could play a role in ...

The Role Expectations of Eighteen California Community-Junior College Presidents Comparative to Three Associative Reference Groups.

ERIC Educational Resources Information Center

Stamm, Harlan Charles

It was hypothesized that there would be no significant difference in the role expectations of junior college presidents and the expectations of their role by their board presidents, by their administrative deans, by their faculty or senate presidents, or between or among the groups. Forty presidents filled out a Rating Scale for Administrative…

Role-Identity Salience, Purpose and Meaning in Life, and Well-Being among Volunteers

ERIC Educational Resources Information Center

Thoits, Peggy A.

2012-01-01

Theoretically, the more important a role-identity is to a person, the more it should provide a sense of purpose and meaning in life. Believing one's life to be purposeful and meaningful should yield greater mental and physical well-being. These hypotheses are tested with respect to the volunteer role, specifically, Mended Hearts visitor, in which…

Farm-Nonfarm Differentials in Fertility: The Effects of Compositional and Sex-Role Factors.

ERIC Educational Resources Information Center

Johnson, Nan E.; And Others

Data derived from the 1970 National Fertility Study (NFS II included post-married women, information on all compositional factors for each respondent, and an 18-item section on sex-role ideology) were used to test the following hypotheses: farm women are more traditional in sex-role ideology than nonfarm women; the higher the sex-role…

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.

The Role of School Principals in Shaping Children's Values.

PubMed

Berson, Yair; Oreg, Shaul

2016-12-01

Instilling values in children is among the cornerstones of every society. There is wide agreement that beyond academic teaching, schools play an important role in shaping schoolchildren's character, imparting in them values such as curiosity, achievement, benevolence, and citizenship. Despite the importance of this topic, we know very little about whether and how schools affect children's values. In this large-scale longitudinal study, we examined school principals' roles in the development of children's values. We hypothesized that relationships exist between principals' values and changes in children's values through the mediating effect of the school climate. To test our predictions, we collected data from 252 school principals, 3,658 teachers, and 49,401 schoolchildren. A multilevel structural-equation-modeling analysis yielded overall support for our hypotheses. These findings contribute to understanding the development of children's values and the far-reaching impact of leaders' values. They also demonstrate effects of schools on children beyond those on academic achievement.

Breaking the cycle: The effects of role model performance and ideal leadership self-concepts on abusive supervision spillover.

PubMed

Tu, Min-Hsuan; Bono, Joyce E; Shum, Cass; LaMontagne, Liva

2018-03-19

Building on identity theories and social learning theory, we test the notion that new leaders will model the abusive behaviors of their superiors only under certain conditions. Specifically, we hypothesize that new leaders will model abusive supervisory behaviors when (a) abusive superiors are perceived to be competent, based on the performance of their teams and (b) new leaders' ideal leadership self-concepts are high on tyranny or low on sensitivity. Results of an experiment in which we manipulated abusive supervisory behaviors using a professional actor, and created a role change where 93 individuals moved from team member to team leader role, generally support our hypotheses. We found the strongest association between abuse exposure and new leader abuse under conditions where the abusive superior's team performed well and the new team leaders' self-concepts showed low concern for others. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Characterizing the Role of Hep27 in Liver and Colorectal Cancer Stress Tolerance

DTIC Science & Technology

2018-01-01

hepatocellular carcinoma, and its high expression correlates with decreased survival in colon cancers. It was hypothesized that Hep27 overexpression is a...Hep27, is overexpressed in hepatocellular carcinoma, and its high expression correlates with decreased survival in colon cancers. I hypothesize that...text. Examples include original copies of journal articles, reprints of manuscripts and abstracts, a curriculum vitae, patent applications, study questionnaires, and surveys , etc. 15 Nothing to report.

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.

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.

Butyrate plays differential roles in cellular signaling in cancerous HCT116 and noncancerous NCM460 colon cells

USDA-ARS?s Scientific Manuscript database

Butyrate, an intestinal microbiota metabolite of dietary fiber, exhibits chemoprevention effects in colon. However, the mechanistic action of butyrate at the cellular level remains to be determined. We hypothesize that butyrate plays differential roles in cancerous and non-cancerous cells through si...

Sex Role Stereotypes and Attitudes Toward Parental Blame for the Psychological Problems of Children

ERIC Educational Resources Information Center

Kellerman, Jonathan

1974-01-01

In accordance with Ackerman's (1957) conception of blame for disorder as the natural consequence of attribution of responsibility for child rearing, it was hypothesized that the direction of parental responsibility would be directly related to ideas about sex role characteristics of child rearing. (Author)

The Medieval Kingdom Topology: Peer Relations in Kindergarten Children.

ERIC Educational Resources Information Center

Bennett, Andrew; Derervensky, Jeffrey

1995-01-01

Examines the applicability of the medieval kingdom social role topology with kindergarten children and assesses the association between the social roles children assume and seven nonbehavioral variables. Confirmed hypotheses that the topology could be distilled from a sample of kindergarten children (n=173) and that specific nonbehavioral…

Sex Role Socialization Patterns in Selected Societies.

ERIC Educational Resources Information Center

Safilios-Rothschild, Constantina

This document evolved because studies concerning sex role socialization patterns were available from only a limited number of societies. In addition to examining available research findings, the author develops a number of relevant hypotheses with respect to several selected societies--the United States, Russia, Greece, India, and Eastern Europe.…

[Power metabolism from neurons and a glia to the whole brain: norm, pathology and correction].

PubMed

Zil'berter, Iu I; Zil'berter, T M

2012-01-01

The review outlines current state of the thepretical, methodological and applies aspects of brain's energy homeostasis. Authors suggest reconsidering the exclusive role of glucose as an energy substrate (ES) at both neuronal and systemic levels discussing recent research data on qualitative composition of ES pool in the brain. The role of ES alternative to glucose, e.g., lactate and ketone bodies, is examined. The hypotheses of intracellular and astrocyte-neuron lactate shuttles are discussed along with the hypotheses of astrocyte-neuron shuttle of ketone bodies, the selfish brain theory and suppositions on homeostatic versus non-homeostatic ES supply chains. In conclusion, authors argue that exogenous native ES may be used for prevention and treatment of neurodegenerative diseases.

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.

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

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.

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.

Mother Involvement as an Influence on Father Involvement with Early Adolescents

PubMed Central

Pleck, Joseph H.; Hofferth, Sandra L.

2009-01-01

This study hypothesized that father involvement is influenced by mothers' level of involvement as well as by marital conflict, mothers' work hours, and fathers' status as biological or step father. The analysis also tested hypotheses about mother involvement as a potential mediator of the effects of marital conflict and maternal work hours on father involvement, and hypotheses about factors influencing mother involvement. Children aged 10-14 from the NLSY79 who resided with their biological or step father and with their mother reported on each parent's involvement with them. As hypothesized, father involvement was predicted by mother involvement, and the reciprocal influence was not significant. Father involvement was associated with low marital conflict and being a biological father. Mothers' involvement partially mediated the effects of marital conflict on father involvement. If the mediating role of maternal involvement is not taken into account, the effect of marital conflict on father involvement is overestimated. PMID:21776195

Predictors of improved functioning in patients with psychosis: The role of amotivation and defeatist performance beliefs.

PubMed

Pillny, Matthias; Lincoln, Tania M

2016-10-30

Defeatist performance beliefs (DPBs) are associated with the severe impairments in functioning of patients with negative symptoms of schizophrenia. This association has been found to be mediated by amotivation, a core aspect of negative symptoms. Although causality is assumed, longitudinal evidence for this is lacking. The current study aimed to extend previous findings by investigating both cross-sectional and longitudinal associations between DPBs, motivational impairments and functioning in a sample of patients with psychotic disorders (N=58). We hypothesized, that DPBs would be related to functioning in cross-sectional and longitudinal analyses and that this link would be mediated by motivational impairments. Data was assessed at baseline and post-treatment in a trial on the effects of cognitive behavior therapy for psychosis. At baseline, amotivation mediated the association between DPBs and functioning. From baseline to post-treatment, reduction of amotivation was associated with improvement of functioning significantly, whereas reduction of DPBs was unrelated to improvements in functioning or amotivation. The findings suggest that improvement in amotivation accounts for favorable treatment outcomes in regard to functioning but question the causal role of DPBs in negative symptoms and functioning. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Surface Adsorption in Nonpolarizable Atomic Models.

PubMed

Whitmer, Jonathan K; Joshi, Abhijeet A; Carlton, Rebecca J; Abbott, Nicholas L; de Pablo, Juan J

2014-12-09

Many ionic solutions exhibit species-dependent properties, including surface tension and the salting-out of proteins. These effects may be loosely quantified in terms of the Hofmeister series, first identified in the context of protein solubility. Here, our interest is to develop atomistic models capable of capturing Hofmeister effects rigorously. Importantly, we aim to capture this dependence in computationally cheap "hard" ionic models, which do not exhibit dynamic polarization. To do this, we have performed an investigation detailing the effects of the water model on these properties. Though incredibly important, the role of water models in simulation of ionic solutions and biological systems is essentially unexplored. We quantify this via the ion-dependent surface attraction of the halide series (Cl, Br, I) and, in so doing, determine the relative importance of various hypothesized contributions to ionic surface free energies. Importantly, we demonstrate surface adsorption can result in hard ionic models combined with a thermodynamically accurate representation of the water molecule (TIP4Q). The effect observed in simulations of iodide is commensurate with previous calculations of the surface potential of mean force in rigid molecular dynamics and polarizable density-functional models. Our calculations are direct simulation evidence of the subtle but sensitive role of water thermodynamics in atomistic simulations.

CCL2/CCL5 secreted by the stroma induce IL-6/PYK2 dependent chemoresistance in ovarian cancer.

PubMed

Pasquier, Jennifer; Gosset, Marie; Geyl, Caroline; Hoarau-Véchot, Jessica; Chevrot, Audrey; Pocard, Marc; Mirshahi, Massoud; Lis, Raphael; Rafii, Arash; Touboul, Cyril

2018-02-19

Minimal residual disease is the main issue of advanced ovarian cancer treatment. According to the literature and previous results, we hypothesized that Mesenchymal Stromal Cells (MSC) could support this minimal residual disease by protecting ovarian cancer cells (OCC) from chemotherapy. In vitro study confirmed that MSC could induce OCC chemoresistance without contact using transwell setting. Further experiments showed that this induced chemoresistance was dependent on IL-6 OCC stimulation. We combined meticulous in vitro profiling and tumor xenograft models to study the role of IL-6 in MSC/OCC intereactions. We demonstrated that Tocilizumab® (anti-IL-6R therapy) in association with chemotherapy significantly reduced the peritoneal carcinosis index (PCI) than chemotherapy alone in mice xenografted with OCCs+MSCs. Further experiments showed that CCL2 and CCL5 are released by MSC in transwell co-culture and induce OCCs IL-6 secretion and chemoresistance. Finally, we found that IL-6 induced chemoresistance was dependent on PYK2 phosphorylation. These findings highlight the potential key role of the stroma in protecting minimal residual disease from chemotherapy, thus favoring recurrences. Future clinical trials targeting stroma could use anti-IL-6 therapy in association with chemotherapy.

Chlorogenic acid ameliorates alcohol-induced liver injuries through scavenging reactive oxygen species.

PubMed

Kim, Hyunjin; Pan, Jeong Hoon; Kim, Sung Hwan; Lee, Jin Hyup; Park, Jeen-Woo

2018-05-19

The key role of oxidative stress in alcoholic liver disease (ALD) has been established by the large body of evidence from previous studies. Excessive consumption of ethanol induces the production of a variety of reactive oxygen species (ROS) in the liver, such as superoxide, H 2 O 2 , and hydroxyl radical. These products activate oxidant-sensitive signaling cascades and modulators of apoptosis. Because ROS accumulation is closely related to ALD, a number of studies have investigated the benefits of antioxidants. Recent studies demonstrated that polyphenol chlorogenic acid (CGA) has antioxidant properties and health benefits, such as reduction of relative risk of cardiovascular diseases and hepatoprotective effects against acetaminophen toxicity. However, the protective effects of CGA against ALD have not been studied in detail. We hypothesize that CGA plays a role in preventing ALD through its antioxidant properties. In this study, we investigated the protective effects of CGA against liver injuries in vivo. Reduced alcohol-induced-steatosis, apoptotic cell death, and fibrosis due to reduced levels of oxidative stress were observed. These findings suggest that CGA treatment can be an effective approach to attenuate ALD through the suppression of oxidative stress. Copyright © 2018. Published by Elsevier B.V.

δ-Catenin Increases the Stability of EGFR by Decreasing c-Cbl Interaction and Enhances EGFR/Erk1/2 Signaling in Prostate Cancer.

PubMed

Shrestha, Nensi; Shrestha, Hridaya; Ryu, Taeyong; Kim, Hangun; Simkhada, Shishli; Cho, Young-Chang; Park, So-Yeon; Cho, Sayeon; Lee, Kwang-Youl; Lee, Jae-Hyuk; Kim, Kwonseop

2018-04-30

δ-Catenin, a member of the p120-catenin subfamily of armadillo proteins, reportedly increases during the late stage of prostate cancer. Our previous study demonstrates that δ-catenin increases the stability of EGFR in prostate cancer cell lines. However, the molecular mechanism behind δ-catenin-mediated enhanced stability of EGFR was not explored. In this study, we hypothesized that δ-catenin enhances the protein stability of EGFR by inhibiting its lysosomal degradation that is mediated by c-casitas b-lineage lymphoma (c-Cbl), a RING domain E3 ligase. c-Cbl monoubiquitinates EGFR and thus facilitates its internalization, followed by lysosomal degradation. We observed that δ-catenin plays a key role in EGFR stability and downstream signaling. δ-Catenin competes with c-Cbl for EGFR binding, which results in a reduction of binding between c-Cbl and EGFR and thus decreases the ubiquitination of EGFR. This in turn increases the expression of membrane bound EGFR and enhances EGFR/Erk1/2 signaling. Our findings add a new perspective on the role of δ-catenin in enhancing EGFR/Erk1/2 signaling-mediated prostate cancer.

Kin keepers and good providers: influence of gender socialization on well-being among USA birth cohorts.

PubMed

Salari, S; Zhang, W

2006-09-01

Previous research has suggested happiness and distress differ for men and women over the life course, but little attention has focused on whether the predictors of well-being vary for each group. The second wave of the National Survey of Families and Households (NSFH2) data was used to study whether hypothesized differential exposure to traditional gender socialization has influenced perceptions of life achievement, global happiness and depression for adult men and women in distinct USA birth cohorts. Numerous findings illustrated similarity among cohort and gender groups in predictors of well-being. There was also evidence of a change in USA gender socialization, and determinants of the dependent variables varied according to these shifts by sex and cohort membership. For example, in the earliest born cohort, women's happiness was related to frequency of contact with relatives, consistent with the kin keeper role. Assets and income predicted depression and global happiness for older men, suggesting a link between well-being and the good provider role. In the latest born cohorts, not just androgynous, but opposite influences predominated as men and women demonstrated less evidence of traditional socialization shaping their satisfaction with achievements and psychological well-being.

Mediating and/or moderating roles of psychological empowerment.

PubMed

Meng, Lina; Jin, Yi; Guo, Jiajia

2016-05-01

The purpose of this study was to explore the mediating and/or moderating effects of psychological empowerment in the relationship between structural empowerment and burnout among nurses in China. Burnout is prevalent among nurses. Previous studies have found that empowering organizational structures contribute to reduce nurses' burnout. However, little is known about the mediating or moderating role of psychological empowerment in the relationship between structural empowerment and burnout among nurses in China. A cross-sectional design was conducted. A total of 244 nurses participated in this study. The data were collected in March 2013. Multiple regressions were used to test the hypothesized models. Psychological empowerment was found to be a significant mediator of the relationship between structural empowerment and burnout (standardized β=-0.553, Sobel test: z=7.79, p<0.001). The moderating effect of psychological empowerment in that relationship was not verified. Both structural and psychological empowerment negatively correlated with burnout. The psychological empowerment had a mediating effect on burnout. It is important for nurse managers to develop strategies to ensure that empowering structures are in place and to facilitate nurses' perception of psychological empowerment. Copyright © 2015 Elsevier Inc. All rights reserved.

Detecting macroecological patterns in bacterial communities across independent studies of global soils.

PubMed

Ramirez, Kelly S; Knight, Christopher G; de Hollander, Mattias; Brearley, Francis Q; Constantinides, Bede; Cotton, Anne; Creer, Si; Crowther, Thomas W; Davison, John; Delgado-Baquerizo, Manuel; Dorrepaal, Ellen; Elliott, David R; Fox, Graeme; Griffiths, Robert I; Hale, Chris; Hartman, Kyle; Houlden, Ashley; Jones, David L; Krab, Eveline J; Maestre, Fernando T; McGuire, Krista L; Monteux, Sylvain; Orr, Caroline H; van der Putten, Wim H; Roberts, Ian S; Robinson, David A; Rocca, Jennifer D; Rowntree, Jennifer; Schlaeppi, Klaus; Shepherd, Matthew; Singh, Brajesh K; Straathof, Angela L; Bhatnagar, Jennifer M; Thion, Cécile; van der Heijden, Marcel G A; de Vries, Franciska T

2018-02-01

The emergence of high-throughput DNA sequencing methods provides unprecedented opportunities to further unravel bacterial biodiversity and its worldwide role from human health to ecosystem functioning. However, despite the abundance of sequencing studies, combining data from multiple individual studies to address macroecological questions of bacterial diversity remains methodically challenging and plagued with biases. Here, using a machine-learning approach that accounts for differences among studies and complex interactions among taxa, we merge 30 independent bacterial data sets comprising 1,998 soil samples from 21 countries. Whereas previous meta-analysis efforts have focused on bacterial diversity measures or abundances of major taxa, we show that disparate amplicon sequence data can be combined at the taxonomy-based level to assess bacterial community structure. We find that rarer taxa are more important for structuring soil communities than abundant taxa, and that these rarer taxa are better predictors of community structure than environmental factors, which are often confounded across studies. We conclude that combining data from independent studies can be used to explore bacterial community dynamics, identify potential 'indicator' taxa with an important role in structuring communities, and propose hypotheses on the factors that shape bacterial biogeography that have been overlooked in the past.

Negative Body Attitudes and Sexual Dissatisfaction in Men: The Mediating Role of Body Self-Consciousness During Physical Intimacy.

PubMed

van den Brink, Femke; Vollmann, Manja; Sternheim, Lot C; Berkhout, Lotte J; Zomerdijk, Renée A; Woertman, Liesbeth

2018-04-01

Previous research indicated that negative attitudes about the body and appearance are common among men and demonstrated that negative body attitudes are associated with negative sexual experiences. The present study investigated the association between body attitudes and sexual dissatisfaction and the mediating role of body self-consciousness during physical intimacy. In a cross-sectional design, 201 Dutch men completed an online survey regarding body attitudes toward muscularity, body fat, height, and genitals, body self-consciousness during physical intimacy, and sexual dissatisfaction. Hypotheses were tested using correlation analyses and a mediation analysis with body attitudes as predictors, body self-consciousness as mediator, and sexual dissatisfaction as outcome. Correlation analyses showed that negative body attitudes and body self-consciousness during physical intimacy were significantly related to sexual dissatisfaction. The mediation analysis revealed that negative attitudes toward muscularity, body fat, and genitals had indirect effects on sexual dissatisfaction through body self-consciousness during physical intimacy. Negative attitudes toward genitals additionally had a direct effect on sexual dissatisfaction. These findings indicate that body image interventions focused on male body attitudes may be beneficial in improving men's body image, which may ultimately increase sexual satisfaction.

Pathway Analysis in Attention Deficit Hyperactivity Disorder: An Ensemble Approach

PubMed Central

Mooney, Michael A.; McWeeney, Shannon K.; Faraone, Stephen V.; Hinney, Anke; Hebebrand, Johannes; Nigg, Joel T.; Wilmot, Beth

2016-01-01

Despite a wealth of evidence for the role of genetics in attention deficit hyperactivity disorder (ADHD), specific and definitive genetic mechanisms have not been identified. Pathway analyses, a subset of gene-set analyses, extend the knowledge gained from genome-wide association studies (GWAS) by providing functional context for genetic associations. However, there are numerous methods for association testing of gene sets and no real consensus regarding the best approach. The present study applied six pathway analysis methods to identify pathways associated with ADHD in two GWAS datasets from the Psychiatric Genomics Consortium. Methods that utilize genotypes to model pathway-level effects identified more replicable pathway associations than methods using summary statistics. In addition, pathways implicated by more than one method were significantly more likely to replicate. A number of brain-relevant pathways, such as RhoA signaling, glycosaminoglycan biosynthesis, fibroblast growth factor receptor activity, and pathways containing potassium channel genes, were nominally significant by multiple methods in both datasets. These results support previous hypotheses about the role of regulation of neurotransmitter release, neurite outgrowth and axon guidance in contributing to the ADHD phenotype and suggest the value of cross-method convergence in evaluating pathway analysis results. PMID:27004716

Understanding the function of visual short-term memory: transsaccadic memory, object correspondence, and gaze correction.

PubMed

Hollingworth, Andrew; Richard, Ashleigh M; Luck, Steven J

2008-02-01

Visual short-term memory (VSTM) has received intensive study over the past decade, with research focused on VSTM capacity and representational format. Yet, the function of VSTM in human cognition is not well understood. Here, the authors demonstrate that VSTM plays an important role in the control of saccadic eye movements. Intelligent human behavior depends on directing the eyes to goal-relevant objects in the world, yet saccades are very often inaccurate and require correction. The authors hypothesized that VSTM is used to remember the features of the current saccade target so that it can be rapidly reacquired after an errant saccade, a task faced by the visual system thousands of times each day. In 4 experiments, memory-based gaze correction was accurate, fast, automatic, and largely unconscious. In addition, a concurrent VSTM load interfered with memory-based gaze correction, but a verbal short-term memory load did not. These findings demonstrate that VSTM plays a direct role in a fundamentally important aspect of visually guided behavior, and they suggest the existence of previously unknown links between VSTM representations and the occulomotor system. PsycINFO Database Record (c) 2008 APA, all rights reserved.

Stabilizing the boundary between US politics and science: the role of the Office of Technology Transfer as a boundary organization.

PubMed

Guston, D H

1999-02-01

The sociological study of boundary-work and the political-ecomomic approach of principal-agent theory can be complementary ways of examining the relationship between society and science: boundary-work provides the empirical nuance to the principal-agent scheme, and principal-agent theory provides structure to the thick boundary description. This paper motivates this complementarity to examine domestic technology transfer in the USA from the intramural laboratories of the US National Institutes of Health (NIH). It casts US policy for technology transfer in the principal-agent framework, in which politicians attempt to manage the moral hazard of the productivity of research by providing specific incentives to the agents for engaging in measurable research-based innovation. Such incentives alter the previously negotiated boundary between politics and science. The paper identifies the crucial role of the NIH Office of Technology Transfer (OTT) as a boundary organization, which medicates the new boundary negotiations in its routine work, and stabilizes the boundary by performing successfully as an agent for both politicians and scientists. The paper hypothesizes that boundary organizations like OTT are general phenomena at the boundary between politics and science.

Src promotes cutaneous wound healing by regulating MMP-2 through the ERK pathway.

PubMed

Wu, Xue; Yang, Longlong; Zheng, Zhao; Li, Zhenzhen; Shi, Jihong; Li, Yan; Han, Shichao; Gao, Jianxin; Tang, Chaowu; Su, Linlin; Hu, Dahai

2016-03-01

Wound healing is a highly orchestrated, multistep process, and delayed wound healing is a significant symptomatic clinical problem. Keratinocyte migration and re-epithelialization play the most important roles in wound healing, as they determine the rate of wound healing. In our previous study, we found that Src, one of the oldest proto‑oncogenes encoding a membrane-associated, non-receptor protein tyrosine kinase, promotes keratinocyte migration. We therefore hypothesized that Src promotes wound healing through enhanced keratinocyte migration. In order to test this hypothesis, vectors for overexpressing Src and small interfering RNAs (siRNAs) for silencing of Src were used in the present study. We found that the overexpression of Src accelerated keratinocyte migration in vitro and promoted wound healing in vivo without exerting a marked effect on cell proliferation. The extracellular signal-regulated kinase (ERK) and c-Jun N-terminal kinase (JNK) signaling pathways play important roles in Src-accelerated keratinocyte migration. Further experiments demonstrated that Src induced the protein expression of matrix metalloproteinase-2 (MMP-2) and decreased the protein expression of E-cadherin. We suggest that ERK signaling is involved in the Src-mediated regulation of MMP-2 expression. The present study provided evidence that Src promotes keratinocyte migration and cutaneous wound healing, in which the regulation of MMP-2 through the ERK pathway plays an important role, and thus we also demonstrated a potential therapeutic role for Src in cutaneous wound healing.

Genome-wide colonization of gene regulatory elements by G4 DNA motifs

PubMed Central

Du, Zhuo; Zhao, Yiqiang; Li, Ning

2009-01-01

G-quadruplex (or G4 DNA), a stable four-stranded structure found in guanine-rich regions, is implicated in the transcriptional regulation of genes involved in growth and development. Previous studies on the role of G4 DNA in gene regulation mostly focused on genomic regions proximal to transcription start sites (TSSs). To gain a more comprehensive understanding of the regulatory role of G4 DNA, we examined the landscape of potential G4 DNA (PG4Ms) motifs in the human genome and found that G4 motifs, not restricted to those found in the TSS-proximal regions, are bias toward gene-associated regions. Significantly, analyses of G4 motifs in seven types of well-known gene regulatory elements revealed a constitutive enrichment pattern and the clusters of G4 motifs tend to be colocalized with regulatory elements. Considering our analysis from a genome evolutionary perspective, we found evidence that the occurrence and accumulation of certain progenitors and canonical G4 DNA motifs within regulatory regions were progressively favored by natural selection. Our results suggest that G4 DNA motifs are ‘colonized’ in regulatory regions, supporting a likely genome-wide role of G4 DNA in gene regulation. We hypothesize that G4 DNA is a regulatory apparatus situated in regulatory elements, acting as a molecular switch that can modulate the role of the host functional regions, by transition in DNA structure. PMID:19759215

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…

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

Integrating ecosystem studies: A Bayesian comparison of hypotheses

USGS Publications Warehouse

Adkison, Milo D.; Ballachey, Brenda E.; Bodkin, James L.; Holland-Bartels, Leslie E.; Funk, F.; Quinn, T.J.; Heifetz, J.; Ianelli, J.N.; Powers, J.E.; Schweigert, J.F.; Sullivan, P.J.; Zhang, C.-I.

1998-01-01

Ecosystem studies are difficult to interpret because of the complexity and number of pathways that may affect a phenomenon of interest. It is not possible to study all aspects of a problem; thus subjective judgment is required to weigh what has been observed in the context of components that were not studied but may have been important. This subjective judgment is usually a poorly documented and ad hoc addendum to a statistical analysis of the data. We present a Bayesian methodology for documenting, quantifying, and incorporating these necessary subjective elements into an ecosystem study. The end product of this methodology is the probability of each of the competing hypotheses. As an example, this method is applied to an ecosystem study designed to discriminate among competing hypotheses for a low abundance of sea otters at a previously oiled site in Prince William Sound, Alaska.

What is the influence of self-image and perceived parenting role expectations on adolescent fathers' perceived role performance?

PubMed

Jones

2000-05-01

Background: "Adolescent pregnancy is one of the most pressing, persistent, and poignant problems facing society" (Yoos, 1987, p. 247). Manitoba's teen pregnancy rates are among the highest in Canada. Yet, little is known about adolescent fathers and their parenting involvement. The purpose of this descriptive correlational study was to explore variables which may influence teen fathers' participation in parenting.Methods: A convenience sample of 30 adolescent fathers, whose partners were attending an Adolescent Prenatal Clinic, completed two questionnaires: Offer Self-Image-Revised, and Perceived Parenting Role Performance. Guided by family role theory, four hypotheses were examined utilizing a quantitative research method.Results: Data analysis revealed that 30% of these respondents had a low to very low self-image. Pearson's correlation coefficient, which facilitated hypotheses testing, failed to validate a relationship between teen fathers' perceived role performance and self-image, and perceived parenting role expectations. Nevertheless, a moderate negative correlation was noted between teen fathers' self-image and their perceived parenting role expectations (r = -.35, p <.05).Conclusions: These findings contradict the philosophy of family role theory. Results of this study indicated that teen fathers want to be involved in parenting. However, unrealistic expectations and the inability to combine the developmental tasks of adolescence with the responsibilities of fatherhood increase their vulnerability to parenting failure.

Moral disengagement in ethical decision making: a study of antecedents and outcomes.

PubMed

Detert, James R; Treviño, Linda Klebe; Sweitzer, Vicki L

2008-03-01

This article advances understanding of the antecedents and outcomes of moral disengagement by testing hypotheses with 3 waves of survey data from 307 business and education undergraduate students. The authors theorize that 6 individual differences will either increase or decrease moral disengagement, defined as a set of cognitive mechanisms that deactivate moral self-regulatory processes and thereby help to explain why individuals often make unethical decisions without apparent guilt or self-censure (Bandura, 1986). Results support 4 individual difference hypotheses, specifically, that empathy and moral identity are negatively related to moral disengagement, while trait cynicism and chance locus of control orientation are positively related to moral disengagement. Two additional locus of control orientations are not significantly related to moral disengagement. The authors also hypothesize and find that moral disengagement is positively related to unethical decision making. Finally, the authors hypothesize that moral disengagement plays a mediating role between the individual differences they studied and unethical decisions. Their results offer partial support for these mediating hypotheses. The authors discuss the implications of these findings for future research and for practice. Copyright 2008 APA

Insights Into Aspects Behind Internet-Related Disorders in Adolescents: The Interplay of Personality and Symptoms of Adjustment Disorders.

PubMed

Müller, Kai W; Wölfling, Klaus; Beutel, Manfred E; Stark, Birgit; Quiring, Oliver; Aufenanger, Stefan; Schemer, Christian; Weber, Mathias; Reinecke, Leonard

2018-02-01

Problematic Internet use (PIU) that has recently been referred to as Internet-related disorder is a growing health concern. Yet, it is unclear why some adolescents are developing problematic use, whereas others sustain control. Based on previous research, we hypothesize that personality traits (low conscientiousness and high neuroticism) act as predispositions for PIU. We further hypothesize that PIU can be understood as a maladaptive reaction toward critical life events and that these maladaptive reactions are exacerbated by dysfunctional personality traits. The study investigates the prevalence of distinct subtypes of PIU among a sample of adolescents (n = 1,489; 10-17 years). Personality traits (Big Five Inventory-10 [BFI-10]), perceived stress (Perceived Stress Scale 4 [PSS-4]), and their relations to PIU (Scale for the Assessment of Internet and Computer Game Addiction [AICA-S]) were examined. As novel research questions, associations between PIU and adjustment disorders (Adjustment Disorder-New Module [ADNM]-6) and the mediating role of personality were investigated. The prevalence of PIU was 2.5%; girls (3.0%) were more often affected than boys (1.9%). Social networking sites in girls and online games in boys were most often associated with PIU. Low conscientiousness and high neuroticism generally predicted PIU. Significantly more adolescents with PIU (70%) reported critical life events compared with those without PIU (42%). PIU was related to heightened stress and higher adjustment disorder symptoms. These associations were exacerbated by conscientiousness and neuroticism. Although the overall prevalence for PIU is in line with previous studies, it appeared unexpectedly that girls were affected more often than boys. Adjustment disorders and stress showed strong associations with PIU. This bears implications for adapting etiopathological assumptions and early intervention strategies. Copyright © 2017 The Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

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.

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

Protein kinase B/Akt activates c-Jun NH(2)-terminal kinase by increasing NO production in response to shear stress

NASA Technical Reports Server (NTRS)

Go, Y. M.; Boo, Y. C.; Park, H.; Maland, M. C.; Patel, R.; Pritchard, K. A. Jr; Fujio, Y.; Walsh, K.; Darley-Usmar, V.; Jo, H.

2001-01-01

Laminar shear stress activates c-Jun NH(2)-terminal kinase (JNK) by the mechanisms involving both nitric oxide (NO) and phosphatidylinositide 3-kinase (PI3K). Because protein kinase B (Akt), a downstream effector of PI3K, has been shown to phosphorylate and activate endothelial NO synthase, we hypothesized that Akt regulates shear-dependent activation of JNK by stimulating NO production. Here, we examined the role of Akt in shear-dependent NO production and JNK activation by expressing a dominant negative Akt mutant (Akt(AA)) and a constitutively active mutant (Akt(Myr)) in bovine aortic endothelial cells (BAEC). As expected, pretreatment of BAEC with the PI3K inhibitor (wortmannin) prevented shear-dependent stimulation of Akt and NO production. Transient expression of Akt(AA) in BAEC by using a recombinant adenoviral construct inhibited the shear-dependent stimulation of NO production and JNK activation. However, transient expression of Akt(Myr) by using a recombinant adenoviral construct did not induce JNK activation. This is consistent with our previous finding that NO is required, but not sufficient on its own, to activate JNK in response to shear stress. These results and our previous findings strongly suggest that shear stress triggers activation of PI3K, Akt, and endothelial NO synthase, leading to production of NO, which (along with O(2-), which is also produced by shear) activates Ras-JNK pathway. The regulation of Akt, NO, and JNK by shear stress is likely to play a critical role in its antiatherogenic effects.

Glycogen phosphorylase in Acanthamoeba spp.: determining the role of the enzyme during the encystment process using RNA interference.

PubMed

Lorenzo-Morales, Jacob; Kliescikova, Jarmila; Martinez-Carretero, Enrique; De Pablos, Luis Miguel; Profotova, Bronislava; Nohynkova, Eva; Osuna, Antonio; Valladares, Basilio

2008-03-01

Acanthamoeba infections are difficult to treat due to often late diagnosis and the lack of effective and specific therapeutic agents. The most important reason for unsuccessful therapy seems to be the existence of a double-wall cyst stage that is highly resistant to the available treatments, causing reinfections. The major components of the Acanthamoeba cyst wall are acid-resistant proteins and cellulose. The latter has been reported to be the major component of the inner cyst wall. It has been demonstrated previously that glycogen is the main source of free glucose for the synthesis of cellulose in Acanthamoeba, partly as glycogen levels fall during the encystment process. In other lower eukaryotes (e.g., Dictyostelium discoideum), glycogen phosphorylase has been reported to be the main tool used for glycogen breakdown in order to maintain the free glucose levels during the encystment process. Therefore, it was hypothesized that the regulation of the key processes involved in the Acanthamoeba encystment may be similar to the previously reported regulation mechanisms in other lower eukaryotes. The catalytic domain of the glycogen phosphorylase was silenced using RNA interference methods, and the effect of this phenomenon was assessed by light and electron microscopy analyses, calcofluor staining, expression zymogram assays, and Northern and Western blot analyses of both small interfering RNA-treated and control cells. The present report establishes the role of glycogen phosphorylase during the encystment process of Acanthamoeba. Moreover, the obtained results demonstrate that the enzyme is required for cyst wall assembly, mainly for the formation of the cell wall inner layer.

Anger Modulates Influence Hierarchies Within and Between Emotional Reactivity and Regulation Networks

PubMed Central

Jacob, Yael; Gilam, Gadi; Lin, Tamar; Raz, Gal; Hendler, Talma

2018-01-01

Emotion regulation is hypothesized to be mediated by the interactions between emotional reactivity and regulation networks during the dynamic unfolding of the emotional episode. Yet, it remains unclear how to delineate the effective relationships between these networks. In this study, we examined the aforementioned networks’ information flow hierarchy during viewing of an anger provoking movie excerpt. Anger regulation is particularly essential for averting individuals from aggression and violence, thus improving prosocial behavior. Using subjective ratings of anger intensity we differentiated between low and high anger periods of the film. We then applied the Dependency Network Analysis (DEPNA), a newly developed graph theory method to quantify networks’ node importance during the two anger periods. The DEPNA analysis revealed that the impact of the ventromedial prefrontal cortex (vmPFC) was higher in the high anger condition, particularly within the regulation network and on the connections between the reactivity and regulation networks. We further showed that higher levels of vmPFC impact on the regulation network were associated with lower subjective anger intensity during the high-anger cinematic period, and lower trait anger levels. Supporting and replicating previous findings, these results emphasize the previously acknowledged central role of vmPFC in modulating negative affect. We further show that the impact of the vmPFC relies on its correlational influence on the connectivity between reactivity and regulation networks. More importantly, the hierarchy network analysis revealed a link between connectivity patterns of the vmPFC and individual differences in anger reactivity and trait, suggesting its potential therapeutic role. PMID:29681803

Glycogen Phosphorylase in Acanthamoeba spp.: Determining the Role of the Enzyme during the Encystment Process Using RNA Interference▿

PubMed Central

Lorenzo-Morales, Jacob; Kliescikova, Jarmila; Martinez-Carretero, Enrique; De Pablos, Luis Miguel; Profotova, Bronislava; Nohynkova, Eva; Osuna, Antonio; Valladares, Basilio

2008-01-01

Acanthamoeba infections are difficult to treat due to often late diagnosis and the lack of effective and specific therapeutic agents. The most important reason for unsuccessful therapy seems to be the existence of a double-wall cyst stage that is highly resistant to the available treatments, causing reinfections. The major components of the Acanthamoeba cyst wall are acid-resistant proteins and cellulose. The latter has been reported to be the major component of the inner cyst wall. It has been demonstrated previously that glycogen is the main source of free glucose for the synthesis of cellulose in Acanthamoeba, partly as glycogen levels fall during the encystment process. In other lower eukaryotes (e.g., Dictyostelium discoideum), glycogen phosphorylase has been reported to be the main tool used for glycogen breakdown in order to maintain the free glucose levels during the encystment process. Therefore, it was hypothesized that the regulation of the key processes involved in the Acanthamoeba encystment may be similar to the previously reported regulation mechanisms in other lower eukaryotes. The catalytic domain of the glycogen phosphorylase was silenced using RNA interference methods, and the effect of this phenomenon was assessed by light and electron microscopy analyses, calcofluor staining, expression zymogram assays, and Northern and Western blot analyses of both small interfering RNA-treated and control cells. The present report establishes the role of glycogen phosphorylase during the encystment process of Acanthamoeba. Moreover, the obtained results demonstrate that the enzyme is required for cyst wall assembly, mainly for the formation of the cell wall inner layer. PMID:18223117

The deafness gene dfna5 is crucial for ugdh expression and HA production in the developing ear in zebrafish.

PubMed

Busch-Nentwich, Elisabeth; Söllner, Christian; Roehl, Henry; Nicolson, Teresa

2004-02-01

Over 30 genes responsible for human hereditary hearing loss have been identified during the last 10 years. The proteins encoded by these genes play roles in a diverse set of cellular functions ranging from transcriptional regulation to K(+) recycling. In a few cases, the genes are novel and do not give much insight into the cellular or molecular cause for the hearing loss. Among these poorly understood deafness genes is DFNA5. How the truncation of the encoded protein DFNA5 leads to an autosomal dominant form of hearing loss is not clear. In order to understand the biological role of Dfna5, we took a reversegenetic approach in zebrafish. Here we show that morpholino antisense nucleotide knock-down of dfna5 function in zebrafish leads to disorganization of the developing semicircular canals and reduction of pharyngeal cartilage. This phenotype closely resembles previously isolated zebrafish craniofacial mutants including the mutant jekyll. jekyll encodes Ugdh [uridine 5'-diphosphate (UDP)-glucose dehydrogenase], an enzyme that is crucial for production of the extracellular matrix component hyaluronic acid (HA). In dfna5 morphants, expression of ugdh is absent in the developing ear and pharyngeal arches, and HA levels are strongly reduced in the outgrowing protrusions of the developing semicircular canals. Previous studies suggest that HA is essential for differentiating cartilage and directed outgrowth of the epithelial protrusions in the developing ear. We hypothesize that the reduction of HA production leads to uncoordinated outgrowth of the canal columns and impaired facial cartilage differentiation.

Sex Ratios, Economic Power, and Women's Roles: A Theoretical Extension and Empirical Test.

ERIC Educational Resources Information Center

South, Scott J.

1988-01-01

Tested hypotheses concerning sex ratios, women's roles, and economic power with data from 111 countries. Found undersupply of women positively associated with proportion of women who marry and fertility rate; inversely associated with women's average age at marriage, literacy rate, and divorce rate. Suggests women's economic power may counteract…

Employment, Marriage, and Inequality in Health Insurance for Mexican-Origin Women

ERIC Educational Resources Information Center

Montez, Jennifer Karas; Angel, Jacqueline L.; Angel, Ronald J.

2009-01-01

In the United States, a woman's health insurance coverage is largely determined by her employment and marital roles. This research evaluates competing hypotheses regarding how the combination of employment and marital roles shapes insurance coverage among Mexican-origin, non-Hispanic white, and African American women. We use data from the 2004 and…

A Critical Review of the Postulated Role of the Cyanobacterial Metabolite, Beta-N-Methylamino-L-Alanine (BMAA) in Neurodegenerative Disease in Humans

EPA Science Inventory

The compound BMAA (β-N-methylamino-L-alanine) has been hypothesized to play a significant role in four serious neurological diseases in humans: Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) found on Guam, and ALS, parkinsonism, and dementia that occur...

Cross-Talk: The Role of Homophily and Elite Bias in Civic Associations

ERIC Educational Resources Information Center

Weare, Christopher; Musso, Juliet; Jun, Kyu-Nahm

2009-01-01

We examine the manner in which voluntary associations expose individuals to differing perspectives, or "cross-talk." Specifically we develop hypotheses based on the interactive roles of elite bias and homophily in structuring networks of democratic participation and test them on social network data of Los Angeles neighborhood councils.…

How to Promote Innovative Behavior at Work? The Role of Justice and Support within Organizations

ERIC Educational Resources Information Center

Young, Linn D.

2012-01-01

To provide a more developed research model of innovation in organizations, we reconsidered current thinking about the effects of organizational justice on innovative behavior at work. We investigated the mediating role of perceived organizational support (POS) between the two constructs. As hypothesized, empirical results showed that justice…

The Role of Training, Individual Differences and Knowledge Representation in Cognitive-Oriented Task Performance.

ERIC Educational Resources Information Center

Koubek, Richard J.

The roles of training, problem representation, and individual differences on performance of both automated (simple) and controlled (complex) process tasks were studied. The following hypotheses were tested: (1) training and cognitive style affect the representation developed; (2) training and cognitive style affect the development and performance…

Role of Self-Identity and Self-Determination in English Learning among High School Students

ERIC Educational Resources Information Center

Zhou, Wanying; Zhou, Mingming

2018-01-01

A considerable amount of research has investigated the separate roles of motivation and identity in language learning. This study aimed to examine these two important constructs jointly by exploring the relationship between motivation, identity processing styles, and English learning among high school students. The hypotheses were empirically…

Sex Role Socialization and Sex Discrimination: A Synthesis and Critique of the Literature.

ERIC Educational Resources Information Center

Safilios-Rothschild, Constantina

This report presents a synthesis and critique of approximately 850 books, research studies, and journal articles appearing between 1960 and 1978 on sex role socialization and sex discrimination. It also offers a number of hypotheses regarding the emergence, maintenance, and elimination of sex discrimination. This document is presented in six…

The Gender of Child Discourse: Sex Roles and Communicative Styles at a Taiwanese Kindergarten.

ERIC Educational Resources Information Center

Farris, Catherine S.

This research study explores how sex role identity is related to the learning of communication and socialization processes in a Taiwanese kindergarten. The study hypothesized that undifferentiated baby-style verbal and nonverbal communication patterns are superceded with styles that become increasingly gender-linked, and language is viewed as a…

Localization Decisions of Entrepreneurs: The Role of Path Dependency and Market Forces

NASA Astrophysics Data System (ADS)

Pylak, Korneliusz; Majerek, Dariusz

2017-10-01

The purpose of this research is to determine the role of path dependency and market forces in the localization decisions of entrepreneurs from different industries. We hypothesize that most industries develop new entities based on the number of companies from the same industry that already exist in a region. We also hypothesize that entrepreneurs create new entities based on related industries operating within the same knowledge pool. To test these hypotheses, we used the machine learning decision tree method. The input variables are the number of companies from 86 industries located in 2,531 communities in Poland in 2009. The target values are the number of new companies from these industries created in the years 2009-2015. The principal results show that localization decisions are mostly based on demand and supply industries, in which manufacturing industries play crucial role. Path dependency appears in less than half of the industries’ models and thus is not the main factor influencing decisions regarding the creation of new companies. The highest share of path-dependent industries is in manufacturing sector, but the degree of the dependence is lower than in the service sector. The service sector seems to be the least path-dependent, as services usually serve other industries. Competition in industries is a rare factor in new company creation; however, if it appears, it usually shrinks the industry.

I Am So Tired… How Fatigue May Exacerbate Stress Reactions to Psychological Contract Breach

PubMed Central

Achnak, Safâa; Griep, Yannick; Vantilborgh, Tim

2018-01-01

Previous research showed that perceptions of psychological contract (PC) breach have undesirable individual and organizational consequences. Surprisingly, the PC literature has paid little to no attention to the relationship between PC breach perceptions and stress. A better understanding of how PC breach may elicit stress seems crucial, given that stress plays a key role in employees' physical and mental well-being. Based on Conservation of Resources Theory, we suggest that PC breach perceptions represent a perceived loss of valued resources, subsequently leading employees to experience higher stress levels resulting from emerging negative emotions. Moreover, we suggest that this mediated relationship is moderated by initial levels of fatigue, due to fatigue lowering the personal resources necessary to cope with breach events. To tests our hypotheses, we analyzed the multilevel data we obtained from two experience sampling designs (Study 1: 51 Belgian employees; Study 2: 53 US employees). Note that the unit of analysis is “observations” rather than “respondents,” resulting in an effective sample size of 730 (Study 1) and 374 (Study 2) observations. In both studies, we found evidence for the mediating role of negative emotions in the PC breach—stress relationship. In the second study, we also found evidence for the moderating role of fatigue in the mediated PC breach—stress relationship. Implications for research and practice are discussed. PMID:29559935

IgA modulates respiratory dysfunction as a sequela to pulmonary chlamydial infection as neonates

PubMed Central

Lanka, Gopala Krishna Koundinya; Yu, Jieh-Juen; Gong, Siqi; Gupta, Rishein; Mustafa, Shamimunisa B.; Murthy, Ashlesh K.; Zhong, Guangming; Chambers, James P.; Guentzel, M. Neal; Arulanandam, Bernard P.

2016-01-01

Neonatal Chlamydia lung infections are associated with serious sequelae such as asthma and airway hyper-reactivity in children and adults. Our previous studies demonstrated the importance of Th-1 type cytokines, IL-12 and IFN-γ in protection against neonatal pulmonary chlamydial challenge; however, the role of the humoral arm of defense has not been elucidated. We hypothesized that B-cells and IgA, the major mucosal antibody, play a protective role in newborns against development of later life respiratory sequelae to Chlamydia infection. Our studies using neonatal mice revealed that all WT and IgA-deficient (IgA−/−) animals survived a sublethal pulmonary Chlamydia muridarum challenge at one day after birth with similar reduction in bacterial burdens over time. In contrast, all B-cell-deficient (μMT) mice succumbed to infection at the same challenge dose correlating to failure to control bacterial burdens in the lungs. Although IgA may not be important for bacterial clearance, we observed IgA−/− mice displayed greater respiratory dysfunction 5 weeks post challenge. Specifically, comparative respiratory functional analyses revealed a significant shift upward in P–V loops, and higher dynamic resistance in IgA−/− animals. This study provides insight(s) into the protective role of IgA in neonates against pulmonary chlamydial infection induced respiratory pathological sequelae observed later in life. PMID:26755533

Linking human capital and enterprise sustainability in Indonesian medium-sized food manufacturing enterprises: the role of informal knowledge sharing practice

NASA Astrophysics Data System (ADS)

Sunardi, O.

2017-12-01

Medium-sized food manufacturing enterprises in Indonesia are significant in a number of contexts, in terms of their part to the national production (GDP) and their establishment to the employment. In term of their role to national production, manufacturing sector contributes the highest GDP by 85%. In this sector, food manufacturing subsector contributes the highest GDP. Nevertheless, they faced the same common problems: quality of human capital and sustainability issues. Previous government supplementary programs have been established to expand the human capital capability amongst medium enterprises. Adequate amount of fund has been apportioned to develop human capital, though, the medium enterprises sustainability is still in question. This study proposes and examines the human capital role from informal knowledge sharing perspective. By conducting qualitative approach through interviews to four informants in Indonesian medium-sized food manufacturing enterprises, a set of hypotheses is derived from this study for future quantitative study. This study indicates that human capital traits (diverse education background, employee skills, and employee experience) could leverage the practice of informal knowledge sharing. Constructs such as mutual trust and reciprocal intention could play as mediating variables, and cultural interpretation perspective could act as moderating factor to informal knowledge sharing effectiveness. In final, informal knowledge sharing is indicated to play as moderating variable for human capital policy and practice to support enterprise sustainability.

I Am So Tired… How Fatigue May Exacerbate Stress Reactions to Psychological Contract Breach.

PubMed

Achnak, Safâa; Griep, Yannick; Vantilborgh, Tim

2018-01-01

Previous research showed that perceptions of psychological contract (PC) breach have undesirable individual and organizational consequences. Surprisingly, the PC literature has paid little to no attention to the relationship between PC breach perceptions and stress. A better understanding of how PC breach may elicit stress seems crucial, given that stress plays a key role in employees' physical and mental well-being. Based on Conservation of Resources Theory, we suggest that PC breach perceptions represent a perceived loss of valued resources, subsequently leading employees to experience higher stress levels resulting from emerging negative emotions. Moreover, we suggest that this mediated relationship is moderated by initial levels of fatigue, due to fatigue lowering the personal resources necessary to cope with breach events. To tests our hypotheses, we analyzed the multilevel data we obtained from two experience sampling designs (Study 1: 51 Belgian employees; Study 2: 53 US employees). Note that the unit of analysis is "observations" rather than "respondents," resulting in an effective sample size of 730 (Study 1) and 374 (Study 2) observations. In both studies, we found evidence for the mediating role of negative emotions in the PC breach-stress relationship. In the second study, we also found evidence for the moderating role of fatigue in the mediated PC breach-stress relationship. Implications for research and practice are discussed.

Nuclear Function of Smad7 Promotes Myogenesis▿

PubMed Central

Miyake, Tetsuaki; Alli, Nezeka S.; McDermott, John C.

2010-01-01

In the “canonical” view of transforming growth factor β (TGF-β) signaling, Smad7 plays an inhibitory role. While Smad7 represses Smad3 activation by TGF-β, it does not reverse the inhibitory effect of TGF-β on myogenesis, suggesting a different function in myogenic cells. We previously reported a promyogenic role of Smad7 mediated by an interaction with MyoD. Based on this association, we hypothesized a possible nuclear function of Smad7 independent of its role at the level of the receptor. We therefore engineered a chimera of Smad7 with a nuclear localization signal (NLS), which serves to prevent and therefore bypass binding to the TGF-β receptor while concomitantly constitutively localizing Smad7 to the nucleus. This Smad7-NLS did not repress Smad3 activation by TGF-β but did retain its ability to enhance myogenic gene activation and phenotypic myogenesis, indicating that the nuclear, receptor-independent function of Smad7 is sufficient to promote myogenesis. Furthermore, Smad7 physically interacts with MyoD and antagonizes the repressive effects of active MEK on MyoD. Reporter and myogenic conversion assays indicate a pivotal regulation of MyoD transcriptional properties by the balance between Smad7 and active MEK. Thus, Smad7 has a nuclear coactivator function that is independent of TGF-β signaling and necessary to promote myogenic differentiation. PMID:19995910

Chromosomal Translocations in the Parasite Leishmania by a MRE11/RAD50-Independent Microhomology-Mediated End Joining Mechanism

PubMed Central

Laffitte, Marie-Claude N.; Leprohon, Philippe; Hainse, Maripier; Légaré, Danielle; Masson, Jean-Yves; Ouellette, Marc

2016-01-01

The parasite Leishmania often relies on gene rearrangements to survive stressful environments. However, safeguarding a minimum level of genome integrity is important for cell survival. We hypothesized that maintenance of genomic integrity in Leishmania would imply a leading role of the MRE11 and RAD50 proteins considering their role in DNA repair, chromosomal organization and protection of chromosomes ends in other organisms. Attempts to generate RAD50 null mutants in a wild-type background failed and we provide evidence that this gene is essential. Remarkably, inactivation of RAD50 was possible in a MRE11 null mutant that we had previously generated, providing good evidence that RAD50 may be dispensable in the absence of MRE11. Inactivation of the MRE11 and RAD50 genes led to a decreased frequency of homologous recombination and analysis of the null mutants by whole genome sequencing revealed several chromosomal translocations. Sequencing of the junction between translocated chromosomes highlighted microhomology sequences at the level of breakpoint regions. Sequencing data also showed a decreased coverage at subtelomeric locations in many chromosomes in the MRE11-/-RAD50-/- parasites. This study demonstrates an MRE11-independent microhomology-mediated end-joining mechanism and a prominent role for MRE11 and RAD50 in the maintenance of genomic integrity. Moreover, we suggest the possible involvement of RAD50 in subtelomeric regions stability. PMID:27314941

Salicylic acid regulates basal resistance to Fusarium head blight in wheat.

PubMed

Makandar, Ragiba; Nalam, Vamsi J; Lee, Hyeonju; Trick, Harold N; Dong, Yanhong; Shah, Jyoti

2012-03-01

Fusarium head blight (FHB) is a destructive disease of cereal crops such as wheat and barley. Previously, expression in wheat of the Arabidopsis NPR1 gene (AtNPR1), which encodes a key regulator of salicylic acid (SA) signaling, was shown to reduce severity of FHB caused by Fusarium graminearum. It was hypothesized that SA signaling contributes to wheat defense against F. graminearum. Here, we show that increased accumulation of SA in fungus-infected spikes correlated with elevated expression of the SA-inducible pathogenesis-related 1 (PR1) gene and FHB resistance. In addition, FHB severity and mycotoxin accumulation were curtailed in wheat plants treated with SA and in AtNPR1 wheat, which is hyper-responsive to SA. In support of a critical role for SA in basal resistance to FHB, disease severity was higher in wheat expressing the NahG-encoded salicylate hydroxylase, which metabolizes SA. The FHB-promoting effect of NahG was overcome by application of benzo (1,2,3), thiadiazole-7 carbothioic acid S-methyl ester, a synthetic functional analog of SA, thus confirming an important role for SA signaling in basal resistance to FHB. We further demonstrate that jasmonate signaling has a dichotomous role in wheat interaction with F. graminearum, constraining activation of SA signaling during early stages of infection and promoting resistance during the later stages of infection.

Emotional intelligence and job performance: The mediating role of work-family balance.

PubMed

Weinzimmer, Laurence G; Baumann, Heidi M; Gullifor, Daniel P; Koubova, Veronika

2017-01-01

In this study, we examine the dynamics between emotional intelligence, work-family balance, and job performance. A review of the literature to date has shown distinct relationships between emotional intelligence to job performance and work-family balance to job performance. We utilize a sample of 233 respondents to empirically test our set of hypotheses that contend work-family balance mediates the relationship between emotional intelligence and job performance. Our results support these hypotheses. Practical implications and directions for future research are discussed.

Why Do Sex Chromosomes Stop Recombining?

PubMed

Ponnikas, Suvi; Sigeman, Hanna; Abbott, Jessica K; Hansson, Bengt

2018-04-28

It is commonly assumed that sex chromosomes evolve recombination suppression because selection favours linkage between sex-determining and sexually antagonistic genes. However, although the role of sexual antagonism during sex chromosome evolution has attained strong support from theory, experimental and observational evidence is rare or equivocal. Here, we highlight alternative, often neglected, hypotheses for recombination suppression on sex chromosomes, which invoke meiotic drive, heterozygote advantage, and genetic drift, respectively. We contrast the hypotheses, the situations when they are likely to be of importance, and outline why it is surprisingly difficult to test them. Lastly, we discuss future research directions (including modelling, population genomics, comparative approaches, and experiments) to disentangle the different hypotheses of sex chromosome evolution. Copyright © 2018 Elsevier Ltd. All rights reserved.

Parental influence on adolescents' imagination.

PubMed

Rabinowitz, A; Engelberg, D

1984-09-01

It was hypothesized that a permissive democratic parental attitude towards childrearing and favorable accepting attitude towards children's imagination are conducive to the development of their adolescent children's imaginative ability. It was also hypothesized that the mothers' role is more crucial than that of the fathers. The subjects were 104 adolescent Israeli boys and girls and their parents. The subjects were administered four scales of the Imaginal Processes Inventory and the Children's Report of Parental Behavior Inventory. The parents filled out a questionnaire devised to study their attitude to children's imagination. The first two hypotheses were not confirmed. The data point in the opposite direction as regards the first hypothesis. There was partial conformation for the third hypothesis. The data were also discussed in relation to healthy and neurotic daydreaming.

Family stress and parental responses to children's negative emotions: tests of the spillover, crossover, and compensatory hypotheses.

PubMed

Nelson, Jackie A; O'Brien, Marion; Blankson, A Nayena; Calkins, Susan D; Keane, Susan P

2009-10-01

The relations between 4 sources of family stress (marital dissatisfaction, home chaos, parental depressive symptoms, and job role dissatisfaction) and the emotion socialization practice of mothers' and fathers' responses to children's negative emotions were examined. Participants included 101 couples with 7-year-old children. Dyadic analyses were conducted using the Actor-Partner Interdependence Model and relations were tested in terms of the spillover, crossover, and compensatory hypotheses. Results suggest that measures of family stress relate to supportive and nonsupportive parental responses, though many of these relations differ by parent gender. The results are discussed in terms of the 3 theoretical hypotheses, all of which are supported to some degree depending on the family stressor examined.

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

Longitudinal analysis of large social networks: Estimating the effect of health traits on changes in friendship ties

PubMed Central

O'Malley, A James; Christakis, Nicholas A

2011-01-01

We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation. Copyright © 2011 John Wiley & Sons, Ltd. PMID:21287589

Biomedical discovery acceleration, with applications to craniofacial development.

PubMed

Leach, Sonia M; Tipney, Hannah; Feng, Weiguo; Baumgartner, William A; Kasliwal, Priyanka; Schuyler, Ronald P; Williams, Trevor; Spritz, Richard A; Hunter, Lawrence

2009-03-01

The profusion of high-throughput instruments and the explosion of new results in the scientific literature, particularly in molecular biomedicine, is both a blessing and a curse to the bench researcher. Even knowledgeable and experienced scientists can benefit from computational tools that help navigate this vast and rapidly evolving terrain. In this paper, we describe a novel computational approach to this challenge, a knowledge-based system that combines reading, reasoning, and reporting methods to facilitate analysis of experimental data. Reading methods extract information from external resources, either by parsing structured data or using biomedical language processing to extract information from unstructured data, and track knowledge provenance. Reasoning methods enrich the knowledge that results from reading by, for example, noting two genes that are annotated to the same ontology term or database entry. Reasoning is also used to combine all sources into a knowledge network that represents the integration of all sorts of relationships between a pair of genes, and to calculate a combined reliability score. Reporting methods combine the knowledge network with a congruent network constructed from experimental data and visualize the combined network in a tool that facilitates the knowledge-based analysis of that data. An implementation of this approach, called the Hanalyzer, is demonstrated on a large-scale gene expression array dataset relevant to craniofacial development. The use of the tool was critical in the creation of hypotheses regarding the roles of four genes never previously characterized as involved in craniofacial development; each of these hypotheses was validated by further experimental work.

Testing the mate-choice hypothesis of the female orgasm: disentangling traits and behaviours.

PubMed

Sherlock, James M; Sidari, Morgan J; Harris, Emily Ann; Barlow, Fiona Kate; Zietsch, Brendan P

2016-01-01

The evolution of the female orgasm in humans and its role in romantic relationships is poorly understood. Whereas the male orgasm is inherently linked to reproduction, the female orgasm is not linked to obvious reproductive or survival benefits. It also occurs less consistently during penetrative sex than does the male orgasm. Mate-choice hypotheses posit that the wide variation in female orgasm frequency reflects a discriminatory mechanism designed to select high-quality mates. We aimed to determine (1) whether women report that their orgasm frequency varies between partners, (2) whether this variation reflects mates' personal characteristics, and (3) whether this variation reflects own and partner sexual behaviour during intercourse. We collected survey data from 103 women who rated (1) the extent to which their orgasm frequency varied between partners, (2) the characteristics of previous sexual partners who induced high-orgasm frequency and those who induced low-orgasm frequency, and (3) the specific behaviours during sex with those partners. This is the first study to test within-woman variation in orgasm and partner traits. Overall, women reported variation in their orgasm rates with different partners. Partners who induced high-orgasm rates were rated as more humorous, creative, warm, faithful, and better smelling than partners who induced low-orgasm rates, and also engaged in greater efforts to induce partner orgasm. Some assumptions and predictions of mate-choice hypotheses of female orgasm were supported, while other aspects of our findings provide reasons to remain sceptical.

Longitudinal analysis of large social networks: estimating the effect of health traits on changes in friendship ties.

PubMed

O'Malley, A James; Christakis, Nicholas A

2011-04-30

We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation. Copyright © 2011 John Wiley & Sons, Ltd.

Intestinal protozoa are hypothesized to stimulate immunosurveillance against colon cancer.

PubMed

Juckett, David A; Aylsworth, Charles F; Quensen, Janet Murphy

2008-01-01

Colon cancer in humans results in considerable morbidity and mortality throughout most of the world. During the twentieth century, there was a rapid rise in colon cancer within modernizing countries that has not been adequately explained, although the role of diet has been widely explored. Previously, we showed that the presence of the endemic Eimeria spp. protozoan in intestinal tissues is associated with regions of low tumorigenesis in the large and small bovine intestine and that an Eimeria surface protein is a potent activator of dendritic cells and a useful immunomodulator, with anti-cancer and anti-viral properties. Therefore, we hypothesize that the persistent presence of such an intestinal protozoan enhances immunosurveillance by elevating the intestinal alert status and that the loss of these organisms could lead to a higher incidence of colon cancer. Preliminary support of this hypothesis derives from the observations that domestic animals, known to maintain this protozoan, have very low colon cancer incidence. We propose that this also may occur in human populations that use human excrement (night soil) as a fertilizer, a practice that serves to complete the life cycle of this type of microbe. We examine some evidence for this hypothesis in Japan's mortality patterns, where we show that colon cancer increased after the cessation of night soil use, but before the change to a western diet. We conclude that this hypothesis, a variation of the hygiene hypothesis, is worth further consideration and continued elaboration.

Testing the mate-choice hypothesis of the female orgasm: disentangling traits and behaviours

PubMed Central

Sherlock, James M.; Sidari, Morgan J.; Harris, Emily Ann; Barlow, Fiona Kate; Zietsch, Brendan P.

2016-01-01

Background The evolution of the female orgasm in humans and its role in romantic relationships is poorly understood. Whereas the male orgasm is inherently linked to reproduction, the female orgasm is not linked to obvious reproductive or survival benefits. It also occurs less consistently during penetrative sex than does the male orgasm. Mate-choice hypotheses posit that the wide variation in female orgasm frequency reflects a discriminatory mechanism designed to select high-quality mates. Objective We aimed to determine (1) whether women report that their orgasm frequency varies between partners, (2) whether this variation reflects mates' personal characteristics, and (3) whether this variation reflects own and partner sexual behaviour during intercourse. Design We collected survey data from 103 women who rated (1) the extent to which their orgasm frequency varied between partners, (2) the characteristics of previous sexual partners who induced high-orgasm frequency and those who induced low-orgasm frequency, and (3) the specific behaviours during sex with those partners. This is the first study to test within-woman variation in orgasm and partner traits. Results Overall, women reported variation in their orgasm rates with different partners. Partners who induced high-orgasm rates were rated as more humorous, creative, warm, faithful, and better smelling than partners who induced low-orgasm rates, and also engaged in greater efforts to induce partner orgasm. Conclusions Some assumptions and predictions of mate-choice hypotheses of female orgasm were supported, while other aspects of our findings provide reasons to remain sceptical. PMID:27791967

Why do niches develop in Caesarean uterine scars? Hypotheses on the aetiology of niche development

PubMed Central

Vervoort, A.J.M.W.; Uittenbogaard, L.B.; Hehenkamp, W.J.K.; Brölmann, H.A.M.; Mol, B.W.J.; Huirne, J.A.F.

2015-01-01

Caesarean section (CS) results in the occurrence of the phenomenon ‘niche’. A ‘niche’ describes the presence of a hypoechoic area within the myometrium of the lower uterine segment, reflecting a discontinuation of the myometrium at the site of a previous CS. Using gel or saline instillation sonohysterography, a niche is identified in the scar in more than half of the women who had had a CS, most with the uterus closed in one single layer, without closure of the peritoneum. An incompletely healed scar is a long-term complication of the CS and is associated with more gynaecological symptoms than is commonly acknowledged. Approximately 30% of women with a niche report spotting at 6–12 months after their CS. Other reported symptoms in women with a niche are dysmenorrhoea, chronic pelvic pain and dyspareunia. Given the association between a niche and gynaecological symptoms, obstetric complications and potentially with subfertility, it is important to elucidate the aetiology of niche development after CS in order to develop preventive strategies. Based on current published data and our observations during sonographic, hysteroscopic and laparoscopic evaluations of niches we postulate some hypotheses on niche development. Possible factors that could play a role in niche development include a very low incision through cervical tissue, inadequate suturing technique during closure of the uterine scar, surgical interventions that increase adhesion formation or patient-related factors that impair wound healing or increase inflammation or adhesion formation. PMID:26409016

Adolescent neural response to reward is related to participant sex and task motivation

PubMed Central

Alarcón, Gabriela; Cservenka, Anita; Nagel, Bonnie J.

2017-01-01

Risky decision making is prominent during adolescence, perhaps contributed to by heightened sensation seeking and ongoing maturation of reward and dopamine systems in the brain, which are, in part, modulated by sex hormones. In this study, we examined sex differences in the neural substrates of reward sensitivity during a risky decision-making task and hypothesized that compared with girls, boys would show heightened brain activation in reward-relevant regions, particularly the nucleus accumbens, during reward receipt. Further, we hypothesized that testosterone and estradiol levels would mediate this sex difference. Moreover, we predicted boys would make more risky choices on the task. While boys showed increased nucleus accumbens blood oxygen level-dependent (BOLD) response relative to girls, sex hormones did not mediate this effect. As predicted, boys made a higher percentage of risky decisions during the task. Interestingly, boys also self-reported more motivation to perform well and earn money on the task, while girls self-reported higher state anxiety prior to the scan session. Motivation to earn money partially mediated the effect of sex on nucleus accumbens activity during reward. Previous research shows that increased motivation and salience of reinforcers is linked with more robust striatal BOLD response, therefore psychosocial factors, in addition to sex, may play an important role in reward sensitivity. Elucidating neurobiological mechanisms that support adolescent sex differences in risky decision making has important implications for understanding individual differences that lead to advantageous and adverse behaviors that affect health outcomes. PMID:27816780

Storing maternal memories: Hypothesizing an interaction of experience and estrogen on sensory cortical plasticity to learn infant cues

PubMed Central

Banerjee, Sunayana B.; Liu, Robert C.

2013-01-01

Much of the literature on maternal behavior has focused on the role of infant experience and hormones in a canonical subcortical circuit for maternal motivation and maternal memory. Although early studies demonstrated that the cerebral cortex also plays a significant role in maternal behaviors, little has been done to explore what that role may be. Recent work though has provided evidence that the cortex, particularly sensory cortices, contains correlates of sensory memories of infant cues, consistent with classical studies of experience-dependent sensory cortical plasticity in non-maternal paradigms. By reviewing the literature from both the maternal behavior and sensory cortical plasticity fields, focusing on the auditory modality, we hypothesize that maternal hormones (predominantly estrogen) may act to prime auditory cortical neurons for a longer-lasting neural trace of infant vocal cues, thereby facilitating recognition and discrimination. This could then more efficiently activate the subcortical circuit to elicit and sustain maternal behavior. PMID:23916405

Parent Emotion Socialization Practices and Child Self-regulation as Predictors of Child Anxiety: The Mediating Role of Cardiac Variability.

PubMed

Williams, Sarah R; Woodruff-Borden, Janet

2015-08-01

The importance of the parent-child relationship in emotional development is well supported. The parental role of facilitating a child's self-regulation may provide a more focused approach for examining the role of parenting in child anxiety. The current study hypothesized that parent emotion socialization practices would predict a child's abilities in self-regulation. Given that physiological arousal has been implicated in emotional development, this was hypothesized to mediate the relationship between parental emotion socialization and child emotion regulation to predict child anxiety. Eighty-five parent and child dyads participated in the study. Parents reporting higher degrees of unsupportive emotion socialization were more likely to have children with fewer abilities in emotion regulation. Cardiac responsiveness mediated the relationship between unsupportive emotion socialization and child emotion regulation. The model of cardiac responsiveness mediating the relationship between unsupportive emotion socialization and child emotion regulation failed to reach statistical significance in predicting child anxiety symptoms.

Building a self-regulatory model of sleep deprivation and deception: the role of caffeine and social influence.

PubMed

Welsh, David T; Ellis, Aleksander P J; Christian, Michael S; Mai, Ke Michael

2014-11-01

Employees are getting less sleep, which has been shown to deplete self-regulatory resources and increase unethical behavior (Barnes, Schaubroeck, Huth, & Ghumman, 2011; Christian & Ellis, 2011). In this study, we extend the original mediated model by examining the role of 2 moderators in the relationship between sleep deprivation, depletion, and deceptive behavior. First, we derive psychological arguments from the psychopharmacology literature to hypothesize that caffeine moderates the relationship between sleep deprivation and depletion by replenishing self-regulatory resources. Second, we draw from recent research in social psychology to hypothesize that social influence moderates the relationship between depletion and deceptive behavior, such that depleted individuals are less able to resist the negative influence of others. Results of a laboratory study provide support for our expanded model combining mediation and moderation, adding to our understanding of the role of sleep deprivation in the incidence of workplace deception. (PsycINFO Database Record (c) 2014 APA, all rights reserved).

Ethnicity- and socio-economic status-related stresses in context: an integrative review and conceptual model.

PubMed

Myers, Hector F

2009-02-01

There continues to be debate about how best to conceptualize and measure the role of exposure to ethnicity-related and socio-economic status-related stressors (e.g. racism, discrimination, class prejudice) in accounting for ethnic health disparities over the lifecourse and across generations. In this review, we provide a brief summary of the evidence of health disparities among ethnic groups, and the major evidence on the role of exposure to ethnicity- and SES-related stressors on health. We then offer a reciprocal and recursive lifespan meta-model that considers the interaction of ethnicity and SES history as impacting exposure to psychosocial adversities, including ethnicity-related stresses, and mediating biopsychosocial mechanisms that interact to result in hypothesized cumulative biopsychosocial vulnerabilities. Ultimately, group differences in the burden of cumulative vulnerabilities are hypothesized as contributing to differential health status over time. Suggestions are offered for future research on the unique role that ethnicity- and SES-related processes are likely to play as contributors to persistent ethnic health disparities.

The stratifying role of job level for sickness absence and the moderating role of gender and occupational gender composition.

PubMed

Kröger, Hannes

2017-08-01

The study investigates whether sickness absence is stratified by job level - understood as the authority and autonomy a worker holds - beyond the association with education, income, and occupation. A second objective is to establish the moderating role of gender and occupational gender composition on this stratification of sickness absence. Four competing hypotheses are developed that predict different patterns of moderation. Associations between job level and sickness absence are estimated for men and women in three groups of differing occupational gender composition, using data from the German Socio-Economic Panel Study (SOEP). For the purpose of moderation analysis, this study employs a new method based on Bayesian statistics, which enables the testing of complex moderation hypotheses. The data support the hypothesis that the stratification of sickness absence by job level is strongest for occupational minorities, meaning men in female-dominated and women in male-dominated occupations. Copyright © 2017 Elsevier Ltd. All rights reserved.

Process tracing in political science: What's the story?

PubMed

Crasnow, Sharon

2017-04-01

Methodologists in political science have advocated for causal process tracing as a way of providing evidence for causal mechanisms. Recent analyses of the method have sought to provide more rigorous accounts of how it provides such evidence. These accounts have focused on the role of process tracing for causal inference and specifically on the way it can be used with case studies for testing hypotheses. While the analyses do provide an account of such testing, they pay little attention to the narrative elements of case studies. I argue that the role of narrative in case studies is not merely incidental. Narrative does cognitive work by both facilitating the consideration of alternative hypotheses and clarifying the relationship between evidence and explanation. I consider the use of process tracing in a particular case (the Fashoda Incident) in order to illustrate the role of narrative. I argue that process tracing contributes to knowledge production in ways that the current focus on inference tends to obscure. Copyright © 2017 Elsevier Ltd. All rights reserved.

Exacerbation of lung radiation injury by viral infection: the role of Clara cells and Clara cell secretory protein.

PubMed

Manning, Casey M; Johnston, Carl J; Hernady, Eric; Miller, Jen-nie H; Reed, Christina K; Lawrence, B Paige; Williams, Jacqueline P; Finkelstein, Jacob N

2013-06-01

Viral infections have been associated with exacerbation of disease in human cases of idiopathic pulmonary fibrosis. Since pulmonary fibrosis is a common outcome after irradiation to the lung, we hypothesized that viral infection after radiation exposure would exacerbate radiation-induced lung injury. Epithelial injury, a frequent outcome after infection, has been hypothesized to contribute to the pathogenesis of pulmonary fibrosis and bronchiolar epithelial Clara cells participate in epithelial repair. Therefore, it was further hypothesized that altered responses after irradiation involve the bronchiolar epithelial Clara cells. C57BL/6J or CCSP(-/-) mice were irradiated with 0 (sham), 5, 10 or 15 Gy to the whole thorax. At ten weeks post-irradiation, animals were mock infected or infected with influenza A virus and body weight and survival were monitored. Pulmonary function was assessed by whole-body plethysmography. The Clara cell markers, CCSP and Cyp2f2, were measured in the lung by qRT-PCR, and protein expression was visualized in the lung by immunofluorescence. Following pulmonary function tests, mice were sacrificed and tissues were collected for pathological analysis. In 15 Gy irradiated animals infected with influenza A virus, accelerated respiratory rates, reduced pulmonary function, and exacerbated lung pathology occurred earlier post-irradiation than previously observed after irradiation alone, suggesting infection accelerates the development of radiation injury. After irradiation alone, CCSP and Cyp2f2 mRNA levels were reduced, correlating with reductions in the number of Clara cells lining the airways. When combined with infection, these markers further declined and an apparent delay in recovery of mRNA expression was observed, suggesting that radiation injury leads to a chronic reduction in the number of Clara cells that may potentiate the epithelial injury observed after influenza A virus infection. This novel finding may have considerable therapeutic implications with respect to both thoracic tumor patients and recipients of bone marrow transplants.

A wet-geology and cold-climate Mars model: Punctuation of a slow dynamic approach to equilibrium

NASA Technical Reports Server (NTRS)

Kargel, J. S.

1993-01-01

It was suggested that Mars may have possessed a relatively warm humid climate and a vigorous hydrological cycle involving meteoric precipitation, oceans, and continental ice sheets. Baker hypothesized that these geologically active conditions may have been repeated several times; each of these dynamic epochs was followed by a collapse of the climate and hydrologic cycle of Mars into essentially current conditions, completing what is termed a 'Baker cycle'. The purpose is to present an endmember possibility that Martian glacial landscapes, including some that were previously considered to have formed under warm climatic conditions, might be explained by processes compatible with an extremely cold surface. Two aspects of hypothesized Martian glacial terrains were cited as favoring a warm climate during Baker cycles: (1) the formation of some landscapes, including possible eskers, tunnel channels, drumlins, and outwash plains, appears to have required liquid water, and (2) a liquid-surfaced ocean was probably necessary to feed the glaciers. The requirement for liquid water, if these features were correctly interpreted, is difficult to avoid; it is entirely possible that a comparatively warm climate was involved, but it is not clear that formation of landforms by wet-based glaciers actually requires a warm climate. Even less certain is the supposed requirement for liquid oceans. Formation of glaciers only requires a source of water or ice to supply an amount of precipitation that exceeds losses due to melting and sublimation. At Martian temperatures precipitation is very low, but so are melting and sublimation, so a large body of ice that is unstable with respect to sublimation may take the role of Earth's oceans in feeding the glaciers. Recent models suggest that even current Martian polar caps, long thought to be static bodies of ice and dust, might actually be slow-moving, cryogenic continental glaciers. Is it possible that subglacial processes beneath cryogenic (but wetbased) ice sheets formed the hypothesized Martian glacial landscapes?

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.

The role of Sphagnum mosses in the methane cycling of a boreal mire.

PubMed

Larmola, Tuula; Tuittila, Eeva-Stiina; Tiirola, Marja; Nykänen, Hannu; Martikainen, Pertti J; Yrjälä, Kim; Tuomivirta, Tero; Fritze, Hannu

2010-08-01

Peatlands are a major natural source of atmospheric methane (CH4). Emissions from Sphagnum-dominated mires are lower than those measured from other mire types. This observation may partly be due to methanotrophic (i.e., methane-consuming) bacteria associated with Sphagnum. Twenty-three of the 41 Sphagnum species in Finland can be found in the peatland at Lakkasuo. To better understand the Sphagnum-methanotroph system, we tested the following hypotheses: (1) all these Sphagnum species support methanotrophic bacteria; (2) water level is the key environmental determinant for differences in methanotrophy across habitats; (3) under dry conditions, Sphagnum species will not host methanotrophic bacteria; and (4) methanotrophs can move from one Sphagnum shoot to another in an aquatic environment. To address hypotheses 1 and 2, we measured the water table and CH4 oxidation for all Sphagnum species at Lakkasuo in 1-5 replicates for each species. Using this systematic approach, we included Sphagnum spp. with narrow and broad ecological tolerances. To estimate the potential contribution of CH4 to moss carbon, we measured the uptake of delta13C supplied as CH4 or as carbon dioxide dissolved in water. To test hypotheses 2-4, we transplanted inactive moss patches to active sites and measured their methanotroph communities before and after transplantation. All 23 Sphagnum species showed methanotrophic activity, confirming hypothesis 1. We found that water level was the key environmental factor regulating methanotrophy in Sphagnum (hypothesis 2). Mosses that previously exhibited no CH4 oxidation became active when transplanted to an environment in which the microbes in the control mosses were actively oxidizing CH4 (hypothesis 4). Newly active transplants possessed a Methylocystis signature also found in the control Sphagnum spp. Inactive transplants also supported a Methylocystis signature in common with active transplants and control mosses, which rejects hypothesis 3. Our results imply a loose symbiosis between Sphagnum spp. and methanotrophic bacteria that accounts for potentially 10-30% of Sphagnum carbon.

Combined effects of exposure to dim light at night and fine particulate matter on C3H/HeNHsd mice.

PubMed

Hogan, Matthew K; Kovalycsik, Taylor; Sun, Qinghua; Rajagopalan, Sanjay; Nelson, Randy J

2015-11-01

Air and light pollution contribute to fetal abnormalities, increase prevalence of cancer, metabolic and cardiorespiratory diseases, and central nervous system (CNS) disorders. A component of air pollution, particulate matter, and the phenomenon of dim light at night (dLAN) both result in neuroinflammation, which has been implicated in several CNS disorders. The combinatorial role of these pollutants on health outcomes has not been assessed. Male C3H/HeNHsd mice, with intact melatonin production, were used to model humans exposed to circadian disruption by dLAN and contaminated environmental air. We hypothesized exposure to 2.5 μm of particulate matter (PM2.5) and dLAN (5lx) combines to upregulate neuroinflammatory cytokine expression and alter hippocampal morphology compared to mice exposed to filtered air (FA) and housed under dark nights (LD). We also hypothesized that exposure to PM2.5 and dLAN provokes anxiety-like and depressive-like responses. For four weeks, four groups of mice were simultaneously exposed to ambient concentrated PM2.5 or FA and/or dLAN or LD. Following exposure, mice underwent several behavioral assays and hippocampi were collected for qPCR and morphological analyses. Our results are generally comparable to previous PM2.5 and dLAN reports conducted on mice and implicate PM2.5 and dLAN as potential factors contributing to depression and anxiety. Short-term exposure to PM2.5 and dLAN upregulated neuroinflammatory cytokines and altered CA1 hippocampal structural changes, as well as provoked depressive-like responses (anhedonia). However, combined, PM2.5 and dLAN exposure did not have additive effects, as hypothesized, suggesting a ceiling effect of neuroinflammation may exist in response to multiple pollutants. Copyright © 2015 Elsevier B.V. All rights reserved.

When more is less: An examination of the relationship between hours in telework and role overload.

PubMed

Duxbury, Linda; Halinski, Michael

2014-01-01

Proponents of telework arrangements assert that those who telework have more control over their work and family domains than their counterparts who are not permitted to work from home. Using Karasek's theory we hypothesized that the relationship between demands (hours in work per week; hours in childcare per week) and strain (work role overload; family role overload) would be moderated by the number of hours the employee spent per week teleworking (control). To determine how the number of telework hours relates to work role overload and family role overload, we follow the test for moderation and mediation using hierarchical multiple regression analysis as outlined by Frazier et al. [50] We used survey data collected from 1,806 male and female professional employees who spent at least one hour per week working from home during regular hours (i.e. teleworking). As hypothesized, the number of hours in telework per week negatively moderated the relation between work demands (total hours in paid employment per week) and work strain (work role overload). Contrary to our hypothesis, the number of hours in telework per week only partially mediated the relation between family demands (hours a week in childcare) and family role overload (strain). The findings from this study support the idea that the control offered by telework is domain specific (helps employees meet demands at work but not at home).

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.

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.

Activation state of the hyperpolarization-activated current modulates temperature-sensitivity of firing in locus coeruleus neurons from bullfrogs.

PubMed

Santin, Joseph M; Hartzler, Lynn K

2015-06-15

Locus coeruleus neurons of anuran amphibians contribute to breathing control and have spontaneous firing frequencies that, paradoxically, increase with cooling. We previously showed that cooling inhibits a depolarizing membrane current, the hyperpolarization-activated current (I h) in locus coeruleus neurons from bullfrogs, Lithobates catesbeianus (Santin JM, Watters KC, Putnam RW, Hartzler LK. Am J Physiol Regul Integr Comp Physiol 305: R1451-R1464, 2013). This suggests an unlikely role for I h in generating cold activation, but led us to hypothesize that inhibition of I h by cooling functions as a physiological brake to limit the cold-activated response. Using whole cell electrophysiology in brain slices, we employed 2 mM Cs(+) (an I h antagonist) to isolate the role of I h in spontaneous firing and cold activation in neurons recorded with either control or I h agonist (cyclic AMP)-containing artificial intracellular fluid. I h did not contribute to the membrane potential (V m) and spontaneous firing at 20°C. Although voltage-clamp analysis confirmed that cooling inhibits I h, its lack of involvement in setting baseline firing and V m precluded its ability to regulate cold activation as hypothesized. In contrast, neurons dialyzed with cAMP exhibited greater baseline firing frequencies at 20°C due to I h activation. Our hypothesis was supported when the starting level of I h was enhanced by elevating cAMP because cold activation was converted to more ordinary cold inhibition. These findings indicate that situations leading to enhancement of I h facilitate firing at 20°C, yet the hyperpolarization associated with inhibiting a depolarizing cation current by cooling blunts the net V m response to cooling to oppose normal cold-depolarizing factors. This suggests that the influence of I h activation state on neuronal firing varies in the poikilothermic neuronal environment. Copyright © 2015 the American Physiological Society.

Modeling Paragenesis: Erosion Opposite to Gravity in Cave Channels

NASA Astrophysics Data System (ADS)

Cooper, M. P.; Covington, M. D.

2017-12-01

Sediment plays an important role in bedrock channels, providing both tools and cover that influence patterns of bed erosion. It has also been shown that sediment load influences bedrock channel width, with increased sediment leading to wider channels. A variety of models have been developed to explore these effects. In caves, it is hypothesized that sediments covering the floors of fully flooded channels that are forming beneath the water table (phreatic zone) can force dissolution upwards towards the water table, leading to upward erosion balanced by gradual deposition of sediment within the channel bottom. This strange process is termed paragenesis, and while there are conceptual and experimental models of the process, no prior mathematical models of cave passage evolution has captured these effects. Consequently, there is little quantitative understanding of the processes that drive paragenesis and how they link to the morphology of the cave channels that develop. We adapt a previously developed algorithm for estimating boundary shear stress within channels with free-surface flows to enable calculation of boundary shear stress in pipe-full conditions. This model successfully duplicates scaling relationships in surface channels, and geometries of caves formed in the phreatic zone such as phreatic tubes. Once sediment flux is incorporated the model successfully duplicates the hypothesized processes of paragenetic gallery formation: the cover effect prevents dissolution in the direction of gravity; passages are enlarged upwards reducing the sediment transport capacity; sediment is deposited and the process drives a continuing feedback loop. Simulations reveal that equilibrium paragenetic channel widths scale with both sediment flux and discharge. Unlike in open channel settings, increased sediment load actually narrows paragenetic channels. The cross section evolution model also reveals that the existence of equilibrium widths in such galleries requires erosion to scale with shear stress, suggesting a role of either mechanical erosion or transport limited dissolution. These types of erosion contrast with current numerical models of speleogenesis, where chemically limited dissolution, a process independent of shear stress, is predicted to occur in most turbulent flow settings.

Benzyl alcohol increases voluntary ethanol drinking in rats.

PubMed

Etelälahti, T J; Eriksson, C J P

2014-09-01

The anabolic steroid nandrolone decanoate has been reported to increase voluntary ethanol intake in Wistar rats. In recent experiments we received opposite results, with decreased voluntary ethanol intake in both high drinking AA and low drinking Wistar rats after nandrolone treatment. The difference between the two studies was that we used pure nandrolone decanoate in oil, whereas in the previous study the nandrolone product Deca-Durabolin containing benzyl alcohol (BA) was used. The aims of the present study were to clarify whether the BA treatment could promote ethanol drinking and to assess the role of the hypothalamic-pituitary-adrenal-gonadal axes (HPAGA) in the potential BA effect. Male AA and Wistar rats received subcutaneously BA or vehicle oil for 14 days. Hereafter followed a 1-week washout and consecutively a 3-week voluntary alcohol consumption period. The median (± median absolute deviation) voluntary ethanol consumption during the drinking period was higher in BA-treated than in control rats (4.94 ± 1.31 g/kg/day vs. 4.17 ± 0.31 g/kg/day, p = 0.07 and 1.01 ± 0.26 g/kg/day vs. 0.38 ± 0.27 g/kg/day, p = 0.05, for AA and Wistar rats, respectively; combined effect p < 0.01). The present results can explain the previous discrepancy between the two nandrolone studies. No significant BA effects on basal and ethanol-mediated serum testosterone and corticosterone levels were observed in blood samples taken at days 1, 8 and 22. However, 2h after ethanol administration significantly (p = 0.02) higher frequency of testosterone elevations was detected in high drinking AA rats compared to low drinking Wistars, which supports our previous hypotheses of a role of testosterone elevation in promoting ethanol drinking. Skin irritation and dermatitis were shown exclusively in the BA-treated animals. Altogether, the present results indicate that earlier findings obtained with Deca-Durabolin containing BA need to be re-evaluated. Copyright © 2014 Elsevier Inc. All rights reserved.

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.

Recognition Memory for Hue: Prototypical Bias and the Role of Labeling

ERIC Educational Resources Information Center

Kelly, Laura Jane; Heit, Evan

2017-01-01

How does the concurrent use of language affect perception and memory for exemplars? Labels cue more general category information than a specific exemplar. Applying labels can affect the resulting memory for an exemplar. Here 3 alternative hypotheses are proposed for the role of labeling an exemplar at encoding: (a) labels distort memory toward the…

EFL Teachers' Teaching Style, Creativity, and Burnout: A Path Analysis Approach

ERIC Educational Resources Information Center

Ghanizadeh, Afsaneh; Jahedizadeh, Safoura

2016-01-01

The present study delved into a rarely explored construct in the domain of English as a foreign language (EFL), i.e. teaching style. We hypothesized that teacher creativity plays a role in the styles teachers adopt in language institutes. It was also conjectured that teaching style affects burnout. The role of burnout in teacher creativity was…

Sexism in Two Editions of a Primary Reading Series.

ERIC Educational Resources Information Center

Garrity, Kathleen

A study compared the 1975 and 1983 editions of the "Macmillan Reading Program Series" primary readers in order to examine sex role portrayals. It was hypothesized that the 1983 edition would show an increase in portrayals of non-sexist roles when compared with the 1975 edition. A checklist was constructed to record instances of sexism…

Exosome-Mediated Pathogen Transmission by Arthropod Vectors.

PubMed

Hackenberg, Michael; Kotsyfakis, Michail

2018-04-24

Recent molecular and cellular studies have highlighted a potentially important role for tick exosomes in parasite transmission. Here we summarize evolving hypotheses about the largely unknown cellular events that may take place at the tick-host-pathogen interface, focusing on a potential role for arthropod exosomes in this tripartite interaction. Copyright © 2018 Elsevier Ltd. All rights reserved.

Lexical Retrieval Constrained by Sound Structure: The Role of the Left Inferior Frontal Gyrus

ERIC Educational Resources Information Center

Sharp, David J.; Scott, Sophie K.; Cutler, Anne; Wise, Richard J. S.

2005-01-01

Positron emission tomography was used to investigate two competing hypotheses about the role of the left inferior frontal gyrus (IFG) in word generation. One proposes a domain-specific organization, with neural activation dependent on the type of information being processed, i.e., surface sound structure or semantic. The other proposes a…

Family Constellation Effects on Interpersonal Trust and Sex Role Orientation among Firstborn and Only Children.

ERIC Educational Resources Information Center

Yee, Elaine F.; And Others

This study examined the effects of birth order on interpersonal trust and sex role orientation among firstborn and only children in late adolescence. The following hypotheses were posed: (1) only children will demonstrate higher degrees of interpersonal trust than firstborn children; (2) only children will show higher degrees of androgyny than…

A critical review of the postulated role of the non-essential amino acid, β-N-methylamino-L-alanine, in neurodegenerative disease in humans

EPA Science Inventory

The compound BMAA (β-N-methylamino-L-alanine) has been hypothesized to play a significant role in four serious neurological diseases in humans: Amyotrophic Lateral Sclerosis/Parkinsonism Dementia Complex (ALS/PDC) found on Guam, and ALS, parkinsonism, and dementia that occur glob...

National Innovation and Knowledge Performance: The Role of Higher Education Teaching and Training

ERIC Educational Resources Information Center

Saad, Mohammed; Guermat, Cherif; Brodie, Lisa

2015-01-01

This paper investigates the role of the higher education system (HES) in the production of national innovation. We focus on the issue of institutional diversity of HESs and its impact on national innovation systems. We identify four key HES characteristics and hypothesize their influence on the production of national innovation. The empirical…

Personality as a Predictor of First-Semester Adjustment to College: The Mediational Role of Perceived Social Support

ERIC Educational Resources Information Center

Lidy, Kara M.; Kahn, Jeffrey H.

2006-01-01

Personality was hypothesized to predict college adjustment because of the role of perceived social support. A sample of III freshmen completed measures of personality, perceived social support, and college adjustment twice in their 1st semester. Perceived social support mediated the relationships between 3 personality factors (Emotional Stability,…

The Role of Self-Efficacy in Performing Emotion Work

ERIC Educational Resources Information Center

Heuven, Ellen; Bakker, Arnold B.; Schaufeli, Wilmar B.; Huisman, Noortje

2006-01-01

This study used a sample of 154 cabin attendants to examine the role of self-efficacy in the performance of emotion work. On the basis of the literature, we hypothesized that self-efficacy would have a moderating influence on the relationship between emotional job demands (i.e., feeling rules and emotionally charged interactions with passengers)…

Role of Parent and Peer Relationships and Individual Characteristics in Middle School Children's Behavioral Outcomes in the Face of Community Violence

ERIC Educational Resources Information Center

Salzinger, Suzanne; Feldman, Richard S.; Rosario, Margaret; Ng-Mak, Daisy S.

2011-01-01

This study examines processes linking inner-city community violence exposure to subsequent internalizing and externalizing problems. Hypothesized risk and protective factors from 3 ecological domains--children's parent and peer relationships and individual characteristics--were examined for mediating, moderating, or independent roles in predicting…

The Role of Health Education on Breast Cancer Awareness among University of Calabar Female Undergraduates

ERIC Educational Resources Information Center

Asuquo, I. M.; Olajide, T. E.

2015-01-01

The study sought to determine the role of health education on breast cancer awareness among University of Calabar female undergraduates. To achieve the purpose of the study, three hypotheses were formulated to guide the study. Related literature was reviewed, while a survey research design was adopted for the study. Appropriately develop and…

Educators' Understanding of the Mediation Role in the Classroom

ERIC Educational Resources Information Center

Ngidi, D. P.

2012-01-01

This study investigated educators' understanding of the mediation role in the classroom. A quantitative research approach was used in a survey of a sample of 261 participants. To this end, a questionnaire was used for collecting data. The Chi-square test was used to analyse data and to test the hypotheses of the study. The findings indicated that…

The Role of Training in Building Employee Commitment: The Mediating Effect of Job Satisfaction

ERIC Educational Resources Information Center

Ocen, Edward; Francis, Kasekende; Angundaru, Gladies

2017-01-01

Purpose: The purpose of this paper is to establish the role of training in building employee commitment and the task of job satisfaction in the association between training and employee commitment in the banking sector in Uganda. Design/methodology/approach: The authors used correlation, regression and MedGraph to investigate the hypotheses.…

The Role of Intelligence in the Formation of Well-Being: From Job Rewards to Job Satisfaction

ERIC Educational Resources Information Center

Ganzach, Yoav; Fried, Itzhak

2012-01-01

In a longitudinal study, we investigate the moderating role of intelligence on the effects of intrinsic and extrinsic rewards and intrinsic and extrinsic satisfactions on global job satisfaction. The results support our hypotheses that: (1) intrinsic rewards and intrinsic satisfaction are more strongly related to global job satisfaction among…

Brain anatomy differences in childhood stuttering.

PubMed

Chang, Soo-Eun; Erickson, Kirk I; Ambrose, Nicoline G; Hasegawa-Johnson, Mark A; Ludlow, Christy L

2008-02-01

Stuttering is a developmental speech disorder that occurs in 5% of children with spontaneous remission in approximately 70% of cases. Previous imaging studies in adults with persistent stuttering found left white matter deficiencies and reversed right-left asymmetries compared to fluent controls. We hypothesized that similar differences might be present indicating brain development differences in children at risk of stuttering. Optimized voxel-based morphometry compared gray matter volume (GMV) and diffusion tensor imaging measured fractional anisotropy (FA) in white matter tracts in 3 groups: children with persistent stuttering, children recovered from stuttering, and fluent peers. Both the persistent stuttering and recovered groups had reduced GMV from normal in speech-relevant regions: the left inferior frontal gyrus and bilateral temporal regions. Reduced FA was found in the left white matter tracts underlying the motor regions for face and larynx in the persistent stuttering group. Contrary to previous findings in adults who stutter, no increases were found in the right hemisphere speech regions in stuttering or recovered children and no differences in right-left asymmetries. Instead, a risk for childhood stuttering was associated with deficiencies in left gray matter volume while reduced white matter integrity in the left hemisphere speech system was associated with persistent stuttering. Anatomical increases in right hemisphere structures previously found in adults who stutter may have resulted from a lifetime of stuttering. These findings point to the importance of considering the role of neuroplasticity during development when studying persistent forms of developmental disorders in adults.

Brain Anatomy Differences in Childhood Stuttering

PubMed Central

Chang, Soo-Eun; Erickson, Kirk I.; Ambrose, Nicoline G.; Hasegawa-Johnson, Mark A.; Ludlow, Christy L.

2009-01-01

Stuttering is a developmental speech disorder that occurs in 5% of children with spontaneous remission in approximately 70% of cases. Previous imaging studies in adults with persistent stuttering found left white matter deficiencies and reversed right-left asymmetries compared to fluent controls. We hypothesized that similar differences might be present indicating brain development differences in children at risk of stuttering. Optimized voxel-based morphometry compared gray matter volume (GMV) and diffusion tensor imaging measured fractional anisotropy (FA) in white matter tracts in 3 groups: children with persistent stuttering, children recovered from stuttering, and fluent peers. Both the persistent stuttering and recovered groups had reduced GMV from normal in speech-relevant regions: the left inferior frontal gyrus, and bilateral temporal regions. Reduced FA was found in the left white matter tracts underlying the motor regions for face and larynx in the persistent stuttering group. Contrary to previous findings in adults who stutter, no increases were found in the right hemisphere speech regions in stuttering or recovered children and no differences in right-left asymmetries. Instead, a risk for childhood stuttering was associated with deficiencies in left gray matter volume while reduced white matter integrity in the left hemisphere speech system was associated with persistent stuttering. Anatomical increases in right hemisphere structures previously found in adults who stutter may have resulted from a life-time of stuttering. These findings point to the importance of considering the role of neuroplasticity during development when studying persistent forms of developmental disorders in adults. PMID:18023366

The Roles of Decision Makers in Special Operations

DTIC Science & Technology

2016-12-01

question and hypotheses. 9 II. CASE STUDIES A. OPERATION THUNDERBOLT (THE RAID ON ENTEBBE) The Israeli Special Forces’ hostage rescue operation...Operations Warfare, 338. 28 Herzog, “The War Against Terrorism: Entebbe,” 338. 29 Chaitanya Arun Sathe, “A Case Study on Crisis Management with a...Assessment of the Roles of Decision Makers This assessment is based on this case study , and the decision makers’ roles in the three phases of a

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.

Searching for ancient balanced polymorphisms shared between Neanderthals and Modern Humans

PubMed Central

Viscardi, Lucas Henriques; Paixão-Côrtes, Vanessa Rodrigues; Comas, David; Salzano, Francisco Mauro; Rovaris, Diego; Bau, Claiton Dotto; Amorim, Carlos Eduardo G.; Bortolini, Maria Cátira

2018-01-01

Abstract Hominin evolution is characterized by adaptive solutions often rooted in behavioral and cognitive changes. If balancing selection had an important and long-lasting impact on the evolution of these traits, it can be hypothesized that genes associated with them should carry an excess of shared polymorphisms (trans- SNPs) across recent Homo species. In this study, we investigate the role of balancing selection in human evolution using available exomes from modern (Homo sapiens) and archaic humans (H. neanderthalensis and Denisovan) for an excess of trans-SNP in two gene sets: one associated with the immune system (IMMS) and another one with behavioral system (BEHS). We identified a significant excess of trans-SNPs in IMMS (N=547), of which six of these located within genes previously associated with schizophrenia. No excess of trans-SNPs was found in BEHS, but five genes in this system harbor potential signals for balancing selection and are associated with psychiatric or neurodevelopmental disorders. Our approach evidenced recent Homo trans-SNPs that have been previously implicated in psychiatric diseases such as schizophrenia, suggesting that a genetic repertoire common to the immune and behavioral systems could have been maintained by balancing selection starting before the split between archaic and modern humans. PMID:29658973

Is outcome responsibility at work emotionally exhausting? Investigating employee proactivity as a moderator.

PubMed

Schmitt, Antje; Den Hartog, Deanne N; Belschak, Frank D

2015-10-01

This study investigates the relationship between outcome responsibility and employees' well-being in terms of emotional exhaustion. Outcome responsibility is a job demand implying that employees' decisions at work have high material and/or nonmaterial consequences. Previous research indicates that outcome responsibility can have both positive and negative effects on employee well-being. Based on the person-job fit approach we hypothesize that whether or not outcome responsibility is positively or negatively related to emotional exhaustion depends on whether employees' behavioral style fits with this job demand. We investigate the role of proactive behavior as a personal resource that fits with high responsibility. We test our hypothesis in a multisource study among 138 employee-colleague dyads. Results of hierarchical moderated regression analysis reveal that peer-rated proactive behavior moderates the relationship between outcome responsibility and emotional exhaustion, such that the relationship is negative for employees showing high and nonsignificant for employees showing low proactivity. This finding holds also when controlling for trait positive and negative affect. The current study contributes to previous research on job design, proactivity, and occupational well-being and offers practical implications in terms of selection and training of employees for jobs high in outcome responsibility. (c) 2015 APA, all rights reserved).

Squid rocket science: How squid launch into air

NASA Astrophysics Data System (ADS)

O'Dor, Ron; Stewart, Julia; Gilly, William; Payne, John; Borges, Teresa Cerveira; Thys, Tierney

2013-10-01

Squid not only swim, they can also fly like rockets, accelerating through the air by forcefully expelling water out of their mantles. Using available lab and field data from four squid species, Sthenoteuthis pteropus, Dosidicus gigas, Illex illecebrosus and Loligo opalescens, including sixteen remarkable photographs of flying S. pteropus off the coast of Brazil, we compared the cost of transport in both water and air and discussed methods of maximizing power output through funnel and mantle constriction. Additionally we found that fin flaps develop at approximately the same size range as flight behaviors in these squids, consistent with previous hypotheses that flaps could function as ailerons whilst aloft. S. pteropus acceleration in air (265 body lengths [BL]/s2; 24.5m/s2) was found to exceed that in water (79BL/s2) three-fold based on estimated mantle length from still photos. Velocities in air (37BL/s; 3.4m/s) exceed those in water (11BL/s) almost four-fold. Given the obvious advantages of this extreme mode of transport, squid flight may in fact be more common than previously thought and potentially employed to reduce migration cost in addition to predation avoidance. Clearly squid flight, the role of fin flaps and funnel, and the energetic benefits are worthy of extended investigation.

Dimethylarginine Dimethylaminohydrolase Overexpression enhances Insulin Sensitivity

PubMed Central

Sydow, Karsten; Mondon, Carl E.; Schrader, Joerg; Konishi, Hakuoh; Cooke, John P.

2011-01-01

Objective Previous studies suggest that nitric oxide (NO) may modulate insulin-induced uptake of glucose in insulin-sensitive tissues. Asymmetric dimethylarginine (ADMA) is an endogenous inhibitor of NO synthase (NOS). We hypothesized that a reduction in endogenous ADMA would increase NO synthesis and thereby enhance insulin sensitivity. Methods and Results To test this hypothesis we employed a transgenic mouse in which we overexpressed human dimethylarginine dimethylaminohydrolase (DDAH-I). The DDAH-I mice had lower plasma ADMA at all ages (22–70 weeks) by comparison to wild-type (WT) littermates. With a glucose challenge, WT mice showed a prompt increase in ADMA, whereas DDAH-I mice had a blunted response. Furthermore, DDAH-I mice had a blunted increase in plasma insulin and glucose levels after glucose challenge, with a 50% reduction in the insulin resistence index, consistent with enhanced sensitivity to insulin. In liver, we observed an increased Akt phosphorylation in the DDAH-I mice after i.p. glucose challenge. Incubation of skeletal muscle from WT mice ex vivo with ADMA (2μM) markedly suppressed insulin-induced glycogen synthesis in fast-twitch but not slow-twitch muscle. Conclusions These findings suggest that the endogenous NOS inhibitor ADMA reduces insulin sensitivity, consistent with previous observations that NO plays a role in insulin sensitivity. PMID:18239148

Using In Vitro Electrophysiology to Screen Medications: Accumbal Plasticity as an Engram of Alcohol Dependence.

PubMed

Renteria, R; Jeanes, Z M; Mangieri, R A; Maier, E Y; Kircher, D M; Buske, T R; Morrisett, R A

2016-01-01

The nucleus accumbens (NAc) is a central component of the mesocorticolimbic reward system. Increasing evidence strongly implicates long-term synaptic neuroadaptations in glutamatergic excitatory activity of the NAc shell and/or core medium spiny neurons in response to chronic drug and alcohol exposure. Such neuroadaptations likely play a critical role in the development and expression of drug-seeking behaviors. We have observed unique cell-type-specific bidirectional changes in NAc synaptic plasticity (metaplasticity) following acute and chronic intermittent ethanol exposure. Other investigators have also previously observed similar metaplasticity in the NAc following exposure to psychostimulants, opiates, and amazingly, even following an anhedonia-inducing experience. Considering that the proteome of the postsynaptic density likely contains hundreds of biochemicals, proteins and other components and regulators, we believe that there is a large number of potential molecular sites through which accumbal metaplasticity may be involved in chronic alcohol abuse. Many of our companion laboratories are now engaged in identifying and screening medications targeting candidate genes and its products previously linked to maladaptive alcohol phenotypes. We hypothesize that if manipulation of such target genes and their products change NAc plasticity, then that observation constitutes an important validation step for the development of novel therapeutics to treat alcohol dependence. © 2016 Elsevier Inc. All rights reserved.

Feeling loved and integrated or lonely and rejected in everyday life: The role of age and social motivation.

PubMed

Nikitin, Jana; Freund, Alexandra M

2018-06-01

Social approach and social avoidance goals (i.e., approach of positive and avoidance of negative outcomes in social situations) are important predictors of the feeling of being socially integrated or isolated. However, little is known about the development of these goals across adulthood. In a large diary study with N = 744 young (18-39 years), middle-aged (40-59 years), and older adults (60-83 years), we tested the hypothesis that the adaptiveness of social goals changes across adulthood: Social approach goals were hypothesized to be adaptive during young adulthood when adult social relationships are to be established. In contrast, social avoidance goals were hypothesized to become more adaptive with age as people are increasingly motivated to avoid interpersonal tension. Our findings support these hypotheses: Social approach goals were positively and social avoidance goals negatively associated with younger but not with middle-aged and older adults' daily social well-being. These results were robust across different situations (positive, negative) and different types of relationships (close, peripheral). The study highlights the changing role of social approach and avoidance goals for daily social well-being across adulthood. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Creativity and inductive reasoning: the relationship between divergent thinking and performance on Wasons 246 task.

PubMed

Vartanian, Oshin; Martindale, Colin; Kwiatkowski, Jonna

2003-05-01

This study was an investigation of the relationship between potential creativityas measured by fluency scores on the Alternate Uses Testand performance on Wasons 246 task. As hypothesized, participants who were successful in discovering the rule had significantly higher fluency scores. Successful participants also generated higher frequencies of confirmatory and disconfirmatory hypotheses, but a multiple regression analysis using the stepwise method revealed that the frequency of generating disconfirmatory hypotheses and fluency scores were the only two significant factors in task outcome. The results also supported earlier studies where disconfirmation was shown to play a more important role in the later stages of hypothesis testing. This was especially true of successful participants, who employed a higher frequency of disconfirmatory hypotheses after receiving feedback on the first announcement. These results imply that successful participants benefited from the provision of feedback on the first announcement by switching to a more successful strategy in the hypothesis-testing sequence.

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 ...

TRAFFIC-RELATED AIR POLLUTANTS AND CHILDREN'S RESPIRATORY HEALTH IN EL PASO AND DETROIT

EPA Science Inventory

Hypotheses -Specific Agent • Diesel exhaust particles • Ultrafine particles • Coarse-mode particles (road dust) • Noise and stress • Nonspecific irritants Previous Epidemiology • Kanawha Valley Health Study • Munich Traffic Study • Dutch Traffic Studies • S....

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…

Triclosan exposure modulates estrogen-dependent responses in the rat uterotrophic assay.

EPA Science Inventory

Our previous studies in the juvenile rat indicated that the biocide triclosan may alter steroid hormone levels. Here, we hypothesize that triclosan possesses estrogenic activity. In the first study, we evaluated the potential estrogenicity of triclosan using the immature rat uter...

Personality Correlates of Machiavellianism: VI. Machiavellianism and the Psychopath.

ERIC Educational Resources Information Center

Skinner, Nicholas F.

1988-01-01

Previous studies have not demonstrated hypothesized link between Machiavellianism (interpersonally manipulative behavior) and psychopathy. Results from two studies using college student samples revealed that High Machs obtained significantly higher Psychopathy scores than did Low Machs, and Mach V totals for Primary Psychopaths were significantly…

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.

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.

Biological determination of mental disorders: a discussion based on recent hypotheses from neuroscience.

PubMed

Freitas-Silva, Luna Rodrigues; Ortega, Francisco

2016-08-29

Understanding the processes involved in the development of mental disorders has proven challenging ever since psychiatry was founded as a field. Neuroscience has provided new expectations that an explanation will be found for the development of mental disorders based on biological functioning alone. However, such a goal has not been that easy to achieve, and new hypotheses have begun to appear in neuroscience research. In this article we identify epigenetics, neurodevelopment, and plasticity as the principal avenues for a new understanding of the biology of mental phenomena. Genetic complexity, the environment's formative role, and variations in vulnerability involve important changes in the principal hypotheses on biological determination of mental disorders, suggesting a reconfiguration of the limits between the "social" and the "biological" in neuroscience research.

Family Stress and Parental Responses to Children’s Negative Emotions: Tests of the Spillover, Crossover, and Compensatory Hypotheses

PubMed Central

Nelson, Jackie A.; O’Brien, Marion; Blankson, A. Nayena; Calkins, Susan D.; Keane, Susan P.

2010-01-01

The relations between 4 sources of family stress (marital dissatisfaction, home chaos, parental depressive symptoms, and job role dissatisfaction) and the emotion socialization practice of mothers’ and fathers’ responses to children’s negative emotions were examined. Participants included 101 couples with 7-year-old children. Dyadic analyses were conducted using the Actor–Partner Interdependence Model and relations were tested in terms of the spillover, crossover, and compensatory hypotheses. Results suggest that measures of family stress relate to supportive and nonsupportive parental responses, though many of these relations differ by parent gender. The results are discussed in terms of the 3 theoretical hypotheses, all of which are supported to some degree depending on the family stressor examined. PMID:19803603

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

Identification and characterization of three Vibrio alginolyticus non-coding RNAs involved in adhesion, chemotaxis, and motility processes.

PubMed

Huang, Lixing; Hu, Jiao; Su, Yongquan; Qin, Yingxue; Kong, Wendi; Ma, Ying; Xu, Xiaojin; Lin, Mao; Yan, Qingpi

2015-01-01

The capability of Vibrio alginolyticus to adhere to fish mucus is a key virulence factor of the bacteria. Our previous research showed that stress conditions, such as Cu(2+), Pb(2+), Hg(2+), and low pH, can reduce this adhesion ability. Non-coding (nc) RNAs play a crucial role in regulating bacterial gene expression, affecting the bacteria's pathogenicity. To investigate the mechanism(s) underlying the decline in adhesion ability caused by stressors, we combined high-throughput sequencing with computational techniques to detect stressed ncRNA dynamics. These approaches yielded three commonly altered ncRNAs that are predicted to regulate the bacterial chemotaxis pathway, which plays a key role in the adhesion process of bacteria. We hypothesized they play a key role in the adhesion process of V. alginolyticus. In this study, we validated the effects of these three ncRNAs on their predicted target genes and their role in the V. alginolyticus adhesion process with RNA interference (i), quantitative real-time polymerase chain reaction (qPCR), northern blot, capillary assay, and in vitro adhesion assays. The expression of these ncRNAs and their predicted target genes were confirmed by qPCR and northern blot, which reinforced the reliability of the sequencing data and the target prediction. Overexpression of these ncRNAs was capable of reducing the chemotactic and adhesion ability of V. alginolyticus, and the expression levels of their target genes were also significantly reduced. Our results indicated that these three ncRNAs: (1) are able to regulate the bacterial chemotaxis pathway, and (2) play a key role in the adhesion process of V. alginolyticus.

Exosomes confer pro-survival signals to alter the phenotype of prostate cells in their surrounding environment

PubMed Central

Hosseini-Beheshti, Elham; Choi, Wendy; Weiswald, Louis-Bastien; Kharmate, Geetanjali; Ghaffari, Mazyar; Roshan-Moniri, Mani; Hassona, Mohamed D.; Chan, Leslie; Chin, Mei Yieng; Tai, Isabella T.; Rennie, Paul S.; Fazli, Ladan; Guns, Emma S. Tomlinson

2016-01-01

Prostate cancer (PCa) is the most frequently diagnosed cancer in men. Current research on tumour-related extracellular vesicles (EVs) suggests that exosomes play a significant role in paracrine signaling pathways, thus potentially influencing cancer progression via multiple mechanisms. In fact, during the last decade numerous studies have revealed the role of EVs in the progression of various pathological conditions including cancer. Moreover, differences in the proteomic, lipidomic, and cholesterol content of exosomes derived from PCa cell lines versus benign prostate cell lines confirm that exosomes could be excellent biomarker candidates. As such, as part of an extensive proteomic analysis using LCMS we previously described a potential role of exosomes as biomarkers for PCa. Current evidence suggests that uptake of EV's into the local tumour microenvironment encouraging us to further examine the role of these vesicles in distinct mechanisms involved in the progression of PCa and castration resistant PCa. For the purpose of this study, we hypothesized that exosomes play a pivotal role in cell-cell communication in the local tumour microenvironment, conferring activation of numerous survival mechanisms during PCa progression and development of therapeutic resistance. Our in vitro results demonstrate that PCa derived exosomes significantly reduce apoptosis, increase cancer cell proliferation and induce cell migration in LNCaP and RWPE-1 cells. In conjunction with our in vitro findings, we have also demonstrated that exosomes increased tumor volume and serum PSA levels in vivo when xenograft bearing mice were administered DU145 cell derived exosomes intravenously. This research suggests that, regardless of androgen receptor phenotype, exosomes derived from PCa cells significantly enhance multiple mechanisms that contribute to PCa progression. PMID:26840259

IL17 Mediates Pelvic Pain in Experimental Autoimmune Prostatitis (EAP).

PubMed

Murphy, Stephen F; Schaeffer, Anthony J; Done, Joseph; Wong, Larry; Bell-Cohn, Ashlee; Roman, Kenny; Cashy, John; Ohlhausen, Michelle; Thumbikat, Praveen

2015-01-01

Chronic pelvic pain syndrome (CPPS) is the most common form of prostatitis, accounting for 90-95% of all diagnoses. It is a complex multi-symptom syndrome with unknown etiology and limited effective treatments. Previous investigations highlight roles for inflammatory mediators in disease progression by correlating levels of cytokines and chemokines with patient reported symptom scores. It is hypothesized that alteration of adaptive immune mechanisms results in autoimmunity and subsequent development of pain. Mouse models of CPPS have been developed to delineate these immune mechanisms driving pain in humans. Using the experimental autoimmune prostatitis (EAP) in C57BL/6 mice model of CPPS we examined the role of CD4+T-cell subsets in the development and maintenance of prostate pain, by tactile allodynia behavioral testing and flow cytometry. In tandem with increased CD4+IL17A+ T-cells upon EAP induction, prophylactic treatment with an anti-IL17 antibody one-day prior to EAP induction prevented the onset of pelvic pain. Therapeutic blockade of IL17 did not reverse pain symptoms indicating that IL17 is essential for development but not maintenance of chronic pain in EAP. Furthermore we identified a cytokine, IL7, to be associated with increased symptom severity in CPPS patients and is increased in patient prostatic secretions and the prostates of EAP mice. IL7 is fundamental to development of IL17 producing cells and plays a role in maturation of auto-reactive T-cells, it is also associated with autoimmune disorders including multiple sclerosis and type-1 diabetes. More recently a growing body of research has pointed to IL17's role in development of neuropathic and chronic pain. This report presents novel data on the role of CD4+IL17+ T-cells in development and maintenance of pain in EAP and CPPS.

Work-family conflict, job satisfaction and spousal support: an exploratory study of nurses' experience.

PubMed

Patel, C J; Beekhan, A; Paruk, Z; Ramgoon, S

2008-03-01

In recognising the highly stressful nature of the nursing profession, the added burden of hospital staff shortages, and patient overload, the present study explored the impact of work on family functioning, its relationship to job satisfaction and the role of spousal support in a group of 80 female nurses working in a government hospital. Using a descriptive, correlational design, the relationships among job satisfaction, work-family conflict (WFC) and spousal/partner support were explored. The hypotheses that job satisfaction and WFC would be negatively correlated, that job satisfaction and spousal support would be positively correlated, and that WFC and spousal support would be negatively correlated, were tested using correlation techniques. All hypotheses were confirmed. The role of spousal support in the relationship between job satisfaction and work -family conflict was highlighted.

Organization structure as a moderator of the relationship between procedural justice, interactional justice, perceived organizational support, and supervisory trust.

PubMed

Ambrose, Maureen L; Schminke, Marshall

2003-04-01

Organizational justice researchers recognize the important role organization context plays in justice perceptions, yet few studies systematically examine contextual variables. This article examines how 1 aspect of context--organizational structure--affects the relationship between justice perceptions and 2 types of social exchange relationships, organizational and supervisory. The authors suggest that under different structural conditions, procedural and interactional justice will play differentially important roles in determining the quality of organizational social exchange (as evidenced by perceived organizational support [POS]) and supervisory social exchange (as evidenced by supervisory trust). In particular, the authors hypothesized that the relationship between procedural justice and POS would be stronger in mechanistic organizations and that the relationship between interactional justice and supervisory trust would be stronger in organic organizations. The authors' results support these hypotheses.

Whole grains beyond fibre: what can metabolomics tell us about mechanisms?

PubMed

Ross, Alastair B

2015-08-01

Dietary fibre alone does not fully explain the frequent association between greater intake of whole grains and reduced risk of disease in observational studies, and other phytochemicals or food structure may also play an important role. For all the observational evidence for the benefits of a whole-grain-rich diet, we have only limited knowledge of the mechanisms behind this reduction in disease risk, aside from the action of specific cereal fibres on reduction of blood cholesterol and the post-prandial glucose peak. Nutritional metabolomics, the global measurement and interpretation of metabolic profiles, assesses the interaction of food with the endogenous gene-protein cascade and the gut microbiome. This approach allows the generation of new hypotheses which account for systemic effects, rather than just focusing on one or two mechanisms or metabolic pathways. To date, animal and human trials using metabolomics to investigate mechanistic changes to metabolism on eating whole grains and cereal fractions have led to new hypotheses around mechanistic effects of whole grains. These include the role of cereals as a major source of dietary glycine betaine, a possible effect on phospholipid synthesis or metabolism, the role of branched-chain amino acids and improvements in insulin sensitivity, and the possibility that whole grains may have an effect on protein metabolism. These hypotheses help explain some of the observed effects of whole grains, although mechanistic studies using stable isotopes and fully quantitative measures are required to confirm these potential mechanisms.

Developmental and evolutionary novelty in the serrated teeth of theropod dinosaurs.

PubMed

Brink, K S; Reisz, R R; LeBlanc, A R H; Chang, R S; Lee, Y C; Chiang, C C; Huang, T; Evans, D C

2015-07-28

Tooth morphology and development can provide valuable insights into the feeding behaviour and evolution of extinct organisms. The teeth of Theropoda, the only clade of predominantly predatory dinosaurs, are characterized by ziphodonty, the presence of serrations (denticles) on their cutting edges. Known today only in varanid lizards, ziphodonty is much more pervasive in the fossil record. Here we present the first model for the development of ziphodont teeth in theropods through histological, SEM, and SR-FTIR analyses, revealing that structures previously hypothesized to prevent tooth breakage instead first evolved to shape and maintain the characteristic denticles through the life of the tooth. We show that this novel complex of dental morphology and tissues characterizes Theropoda, with the exception of species with modified feeding behaviours, suggesting that these characters are important for facilitating the hypercarnivorous diet of most theropods. This adaptation may have played an important role in the initial radiation and subsequent success of theropods as terrestrial apex predators.

Oral transfer of chemical cues, growth proteins and hormones in social insects

PubMed Central

LeBoeuf, Adria C; Waridel, Patrice; Brent, Colin S; Gonçalves, Andre N; Menin, Laure; Ortiz, Daniel; Riba-Grognuz, Oksana; Koto, Akiko; Soares, Zamira G; Privman, Eyal; Miska, Eric A; Benton, Richard; Keller, Laurent

2016-01-01

Social insects frequently engage in oral fluid exchange – trophallaxis – between adults, and between adults and larvae. Although trophallaxis is widely considered a food-sharing mechanism, we hypothesized that endogenous components of this fluid might underlie a novel means of chemical communication between colony members. Through protein and small-molecule mass spectrometry and RNA sequencing, we found that trophallactic fluid in the ant Camponotus floridanus contains a set of specific digestion- and non-digestion related proteins, as well as hydrocarbons, microRNAs, and a key developmental regulator, juvenile hormone. When C. floridanus workers’ food was supplemented with this hormone, the larvae they reared via trophallaxis were twice as likely to complete metamorphosis and became larger workers. Comparison of trophallactic fluid proteins across social insect species revealed that many are regulators of growth, development and behavioral maturation. These results suggest that trophallaxis plays previously unsuspected roles in communication and enables communal control of colony phenotypes. DOI: http://dx.doi.org/10.7554/eLife.20375.001 PMID:27894417

Unusual loss of chymosin in mammalian lineages parallels neo-natal immune transfer strategies.

PubMed

Lopes-Marques, Mónica; Ruivo, Raquel; Fonseca, Elza; Teixeira, Ana; Castro, L Filipe C

2017-11-01

Gene duplication and loss are powerful drivers of evolutionary change. The role of loss in phenotypic diversification is notably illustrated by the variable enzymatic repertoire involved in vertebrate protein digestion. Among these we find the pepsin family of aspartic proteinases, including chymosin (Cmy). Previous studies demonstrated that Cmy, a neo-natal digestive pepsin, is inactivated in some primates, including humans. This pseudogenization event was hypothesized to result from the acquisition of maternal immune immunoglobulin G (IgG) transfer. By investigating 94 mammalian subgenomes we reveal an unprecedented level of Cmy erosion in placental mammals, with numerous independent events of gene loss taking place in Primates, Dermoptera, Rodentia, Cetacea and Perissodactyla. Our findings strongly suggest that the recurrent inactivation of Cmy correlates with the evolution of the passive transfer of IgG and uncovers a noteworthy case of evolutionary cross-talk between the digestive and the immune system, modulated by gene loss. Copyright © 2017 Elsevier Inc. All rights reserved.

Placental and Fetal Disposition of Mercuric Ions in Rats Exposed to Methylmercury: Role of Mrp2

PubMed Central

Bridges, Christy C.; Joshee, Lucy; Zalups, Rudolfs K.

2012-01-01

Methylmercury is a prevalent environmental toxicant that can have deleterious effects on a developing fetus. Previous studies indicate that the multidrug resistance-associated protein 2 (Mrp2) is involved in renal and hepatic export of mercuric ions. Therefore, we hypothesize that Mrp2 is also involved in export of mercuric ions from placental trophoblasts and fetal tissues. To test this hypothesis, we assessed the disposition of mercuric ions in pregnant Wistar and TR– (Mrp2-deficient) rats exposed to a single dose of methylmercury. The amount of mercury in renal tissues (cortex and outer stripe of outer medulla), liver, blood, amniotic fluid, uterus, placentas and fetuses was significantly greater in TR– rats than in Wistar rats. Urinary and fecal elimination of mercury was greater in Wistar dams than in TR– dams. Thus, our findings suggest that Mrp2 may be involved in the export of mercuric ions from maternal and fetal organs following exposure to methylmercury. PMID:23059061

Galactose transport in Kluyveromyces lactis: major role of the glucose permease Hgt1.

PubMed

Baruffini, Enrico; Goffrini, Paola; Donnini, Claudia; Lodi, Tiziana

2006-12-01

In Kluyveromyces lactis, galactose transport has been thought to be mediated by the lactose permease encoded by LAC12. In fact, a lac12 mutant unable to grow on lactose did not grow on galactose either and showed low and uninducible galactose uptake activity. The existence of other galactose transport systems, at low and at high affinity, had, however, been hypothesized on the basis of galactose uptake kinetics studies. Here we confirmed the existence of a second galactose transporter and we isolated its structural gene. It turned out to be HGT1, previously identified as encoding the high-affinity glucose carrier. Analysis of galactose transporter mutants, hgt1 and lac12, and the double mutant hgt1lac12, suggested that Hgt1 was the high-affinity and Lac12 was the low-affinity galactose transporter. HGT1 expression was strongly induced by galactose and insensitive to glucose repression. This could explain the rapid adaptation to galactose observed in K. lactis after a shift from glucose to galactose medium.

How do different types of community commitment influence brand commitment? The mediation of brand attachment.

PubMed

Zhang, Ning; Zhou, Zhi-min; Su, Chen-ting; Zhou, Nan

2013-11-01

Although previous research indicates that participation in a brand community may foster consumer loyalty to the brand in question, research has seldom examined the mediating effect of community commitment on brand commitment. Drawing from the typologies of organizational commitment, we divide community commitment into three components: continuance community commitment (continuance CC), affective community commitment (affective CC), and normative community commitment (normative CC). We then assess the mediating role of brand attachment in the relationship between these three components and brand commitment. We test the hypotheses using a sample of online mobile phone brand communities in China. The empirical results reveal that brand attachment exerts an indirect (but not mediated) effect on the relationship between continuance CC and brand commitment and on the relationship between normative CC and brand commitment. We also find that it exerts a partial mediating effect on the relationship between affective CC and brand commitment. The findings contribute to the branding literature and have important implications for brand community management.

Persistent spatial information in the FEF during object-based short-term memory does not contribute to task performance.

PubMed

Clark, Kelsey L; Noudoost, Behrad; Moore, Tirin

2014-06-01

We previously reported the existence of a persistent spatial signal in the FEF during object-based STM. This persistent activity reflected the location at which the sample appeared, irrespective of the location of upcoming targets. We hypothesized that such a spatial signal could be used to maintain or enhance object-selective memory activity elsewhere in cortex, analogous to the role of a spatial signal during attention. Here, we inactivated a portion of the FEF with GABAa agonist muscimol to test whether the observed activity contributes to object memory performance. We found that, although RTs were slowed for saccades into the inactivated portion of retinotopic space, performance for samples appearing in that region was unimpaired. This contrasts with the devastating effects of the same FEF inactivation on purely spatial working memory, as assessed with the memory-guided saccade task. Thus, in a task in which a significant fraction of FEF neurons displayed persistent, sample location-based activity, disrupting this activity had no impact on task performance.

Unanswered questions on ectopic pregnancy.

PubMed

Jonas, E G

1980-07-19

In a previous article (3 May, p. 1127), the British Medical Journal attempted to assess the demography of ectopic pregnancy and noted that a rise in incidence might lead to a better diagnosis of the condition. Cited as possible causes of ectopic pregnancy are pelvic sepsis and IUD usage. There is clinical confirmation of the relationship between pelvic sepsis and IUD usage. A review of the records of 325 consecutive patients diagnosed as having ectopic pregnancy in 4 large London Hospitals during the period 1967-79 revealed that PID (Pelvic Inflammatory Disease) was uncommon (11%). 12% of the remaining patients had IUDs and a further 2% were progestogen-only contraceptive failures. As regards the role of IUDs in ectopic pregnancy, failed intrauterine contraception is hypothesized to result in pregnancy, but with an incidence of ectopic, mainly tubal, implantation by reasons of disturbed ovum migration along the oviduct. The physiology of the human oviduct is not well known. Further research should be done on the many common aberations of human reproduction, iatrogenic and spontaneous.

How Do Different Types of Community Commitment Influence Brand Commitment? The Mediation of Brand Attachment

PubMed Central

Zhang, Ning; Su, Chen-ting; Zhou, Nan

2013-01-01

Abstract Although previous research indicates that participation in a brand community may foster consumer loyalty to the brand in question, research has seldom examined the mediating effect of community commitment on brand commitment. Drawing from the typologies of organizational commitment, we divide community commitment into three components: continuance community commitment (continuance CC), affective community commitment (affective CC), and normative community commitment (normative CC). We then assess the mediating role of brand attachment in the relationship between these three components and brand commitment. We test the hypotheses using a sample of online mobile phone brand communities in China. The empirical results reveal that brand attachment exerts an indirect (but not mediated) effect on the relationship between continuance CC and brand commitment and on the relationship between normative CC and brand commitment. We also find that it exerts a partial mediating effect on the relationship between affective CC and brand commitment. The findings contribute to the branding literature and have important implications for brand community management. PMID:23768073

Preferences, constraints, and the process of sex segregation in college majors: A choice analysis.

PubMed

Ochsenfeld, Fabian

2016-03-01

The persistence of horizontal sex segregation in higher education continues to puzzle social scientists. To help resolve this puzzle, we analyze a sample of college entrants in Germany with a discrete choice design that allows for social learning from the experiences of others. We make at least two contributions to the state of research. First, we test whether essentialist gender stereotypes affect major selection mostly through internalization or rather as external constraints that high school graduates adapt their behavior to. Empirically, we find that internalized vocational interests better explain gendered major choices than conformance with friends' and parents' expectations does. Second, we scrutinize whether segregation results from women's anticipation of gendered family roles or from their anticipation of sex-based discrimination, but we find no evidence for either of these hypotheses. As in most previous studies, differences in mathematics achievement fail to explain gendered patterns of selection into college majors. Copyright © 2016 Elsevier Inc. All rights reserved.

Standard deviations of composition measurements in atom probe analyses-Part II: 3D atom probe.

PubMed

Danoix, F; Grancher, G; Bostel, A; Blavette, D

2007-09-01

In a companion paper [F. Danoix, G. Grancher, A. Bostel, D. Blavette, Surf. Interface Anal. this issue (previous paper).], the derivation of variances of the estimates of measured composition, and the underlying hypotheses, have been revisited in the the case of conventional one dimensional (1D) atom probes. In this second paper, we will concentrate on the analytical derivation of the variance when the estimate of composition is obtained from a 3D atom probe. As will be discussed, when the position information is available, compositions can be derived either from constant number of atoms, or from constant volume, blocks. The analytical treatment in the first case is identical to the one developed for conventional 1D instruments, and will not be discussed further in this paper. Conversely, in the second case, the analytical treatment is different, as well as the formula of the variance. In particular, it will be shown that the detection efficiency plays an important role in the determination of the variance.

Transcriptional Changes That Characterize the Immune Reactions of Leprosy

PubMed Central

Dupnik, Kathryn M.; Bair, Thomas B.; Maia, Andressa O.; Amorim, Francianne M.; Costa, Marcos R.; Keesen, Tatjana S. L.; Valverde, Joanna G.; Queiroz, Maria do Carmo A. P.; Medeiros, Lúcio L.; de Lucena, Nelly L.; Wilson, Mary E.; Nobre, Mauricio L.; Johnson, Warren D.; Jeronimo, Selma M. B.

2015-01-01

Background. Leprosy morbidity is increased by 2 pathologic immune reactions, reversal reaction (RR) and erythema nodosum leprosum (ENL). Methods. To discover host factors related to immune reactions, global transcriptional profiles of peripheral blood mononuclear cells were compared between 11 RR, 11 ENL, and 19 matched control patients, with confirmation by quantitative polymerase chain reaction. Encoded proteins were investigated in skin biopsy specimens by means of immunohistochemistry. Results. There were 275 genes differentially expressed in RR and 517 differentially expressed in ENL on the microarray. Pathway analysis showed immunity-related pathways represented in RR and ENL transcriptional profiles, with the “complement and coagulation” pathway common to both. Interferon γ was identified as a significant upstream regulator of the expression changes for RR and ENL. Immunohistochemical staining of skin lesions showed increased C1q in both RR and ENL. Conclusions. These data suggest a previously underrecognized role for complement in the pathogenesis of both RR and ENL, and we propose new hypotheses for reaction pathogenesis. PMID:25398459

Factors buffering against the effects of job demands: how does age matter?

PubMed

Besen, Elyssa; Matz-Costa, Christina; James, Jacquelyn B; Pitt-Catsouphes, Marcie

2015-02-01

Given the increasing role that paid work is likely to play in older adulthood in the coming decades, the goal of this study was to understand the circumstances under which work is related to mental health for older adults and whether these circumstances differ by age. Using a multiworksite sample of 1,812 U.S. workers age 18 to 81, we use the life-span theory of control to hypothesize that older and younger workers may benefit differentially from job and personal control in the context of high job demands. Results suggest that for younger workers with high personal control, job control buffers the impact of job demands on mental health. For older workers, personal control alone buffers the impact of job demands on mental health. This study adds to previous research by addressing how the factors thought to buffer against the effects of job demands differ cross-sectionally by age. © The Author(s) 2012.

Sexual aggression when power is new: Effects of acute high power on chronically low-power individuals.

PubMed

Williams, Melissa J; Gruenfeld, Deborah H; Guillory, Lucia E

2017-02-01

Previous theorists have characterized sexually aggressive behavior as an expression of power, yet evidence that power causes sexual aggression is mixed. We hypothesize that power can indeed create opportunities for sexual aggression-but that it is those who chronically experience low power who will choose to exploit such opportunities. Here, low-power men placed in a high-power role showed the most hostility in response to a denied opportunity with an attractive woman (Studies 1 and 2). Chronically low-power men and women given acute power were the most likely to say they would inappropriately pursue an unrequited workplace attraction (Studies 3 and 4). Finally, having power over an attractive woman increased harassment behavior among men with chronic low, but not high, power (Study 5). People who see themselves as chronically denied power appear to have a stronger desire to feel powerful and are more likely to use sexual aggression toward that end. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

The Role of Feared Possible Selves on the Relationship Between Peer Influence and Delinquency

PubMed Central

Pierce, Jennifer; Schmidt, Carissa; Stoddard, Sarah

2014-01-01

This study explores the impact of a feared delinquent possible self on the relationship between exposure to negative peer behaviors and violent and non-violent self-reported delinquency. Previous research strongly supports that deviant peers influence adolescents’ delinquent behavior. Yet, few studies have explored intrapersonal factors that may moderate this influence. Possible selves include what one hopes, expects and fears becoming and are believed to motivate behavior. Thus, it was hypothesized that adolescents who were exposed to deviant peers and also feared engaging in delinquency would be more likely to self-report delinquency. Seventh grade students (n = 176) identified feared possible selves in the future, their exposure to negative peer behavior and self-reported violent and non-violent delinquent behavior. Findings suggest that exposure to negative peer behavior is associated with self-reported delinquent behavior. For violent behavior, possessing a feared delinquent possible self moderates this relationship. Implications and suggestions for future research are discussed. PMID:25460676

A Genetically Defined Circuit for Arousal from Sleep during Hypercapnia.

PubMed

Kaur, Satvinder; Wang, Joshua L; Ferrari, Loris; Thankachan, Stephen; Kroeger, Daniel; Venner, Anne; Lazarus, Michael; Wellman, Andrew; Arrigoni, Elda; Fuller, Patrick M; Saper, Clifford B

2017-12-06

The precise neural circuitry that mediates arousal during sleep apnea is not known. We previously found that glutamatergic neurons in the external lateral parabrachial nucleus (PBel) play a critical role in arousal to elevated CO2 or hypoxia. Because many of the PBel neurons that respond to CO2 express calcitonin gene-related peptide (CGRP), we hypothesized that CGRP may provide a molecular identifier of the CO2 arousal circuit. Here, we report that selective chemogenetic and optogenetic activation of PBel CGRP neurons caused wakefulness, whereas optogenetic inhibition of PBel CGRP neurons prevented arousal to CO2, but not to an acoustic tone or shaking. Optogenetic inhibition of PBel CGRP terminals identified a network of forebrain sites under the control of a PBel CGRP switch that is necessary to arouse animals from hypercapnia. Our findings define a novel cellular target for interventions that may prevent sleep fragmentation and the attendant cardiovascular and cognitive consequences seen in obstructive sleep apnea. VIDEO ABSTRACT. Copyright © 2017 Elsevier Inc. All rights reserved.

Food Insecurity and Chronic Disease123

PubMed Central

Laraia, Barbara A.

2013-01-01

Household food insecurity has been previously hypothesized to promote dependence on inexpensive, highly palatable foods that are energy dense. Such dependence, and the cyclical nature of having enough food in the beginning of the month followed by food scarcity at the end of the month, could lead to weight gain over a short period of time. Such dependence on energy-dense foods and weight gain may play a direct role in the development of chronic conditions. Other compounding factors that result from exposure to household food insecurity have been well described, including pathways by which stress promotes visceral fat accumulation and chronic disease. This symposium review paper summarizes the literature on the link between food insecurity and the following: 1) diet, 2) weight gain, and 3) chronic disease, especially among women. This paper also proposes a framework for considering how the lived experience of household food insecurity may potentiate the development of chronic disease by activating the stress response among individuals at critical developmental periods in a food-impoverished environment. PMID:23493536

Abnormal Glycosphingolipid Mannosylation Triggers Salicylic Acid–Mediated Responses in Arabidopsis[W][OA

PubMed Central

Mortimer, Jenny C.; Yu, Xiaolan; Albrecht, Sandra; Sicilia, Francesca; Huichalaf, Mariela; Ampuero, Diego; Michaelson, Louise V.; Murphy, Alex M.; Matsunaga, Toshiro; Kurz, Samantha; Stephens, Elaine; Baldwin, Timothy C.; Ishii, Tadashi; Napier, Johnathan A.; Weber, Andreas P.M.; Handford, Michael G.; Dupree, Paul

2013-01-01

The Arabidopsis thaliana protein GOLGI-LOCALIZED NUCLEOTIDE SUGAR TRANSPORTER (GONST1) has been previously identified as a GDP-d-mannose transporter. It has been hypothesized that GONST1 provides precursors for the synthesis of cell wall polysaccharides, such as glucomannan. Here, we show that in vitro GONST1 can transport all four plant GDP-sugars. However, gonst1 mutants have no reduction in glucomannan quantity and show no detectable alterations in other cell wall polysaccharides. By contrast, we show that a class of glycosylated sphingolipids (glycosylinositol phosphoceramides [GIPCs]) contains Man and that this mannosylation is affected in gonst1. GONST1 therefore is a Golgi GDP-sugar transporter that specifically supplies GDP-Man to the Golgi lumen for GIPC synthesis. gonst1 plants have a dwarfed phenotype and a constitutive hypersensitive response with elevated salicylic acid levels. This suggests an unexpected role for GIPC sugar decorations in sphingolipid function and plant defense signaling. Additionally, we discuss these data in the context of substrate channeling within the Golgi. PMID:23695979

Homonegativity among first and second generation migrants in Europe: the interplay of time trends, origin, destination and religion.

PubMed

Van der Bracht, Koen; Van de Putte, Bart

2014-11-01

Previous studies reported declining disapproval of homosexuality in Europe but have simultaneously identified the decelerating effect of religiosity and the higher disapproval of homosexuality among migrants. In this paper, we address disapproval of homosexuality among first- and second-generation migrants in Europe by assessing (1) period and cohort changes, (2) origin and destination country influences and (3) the role of religiosity. We develop a specific cross-classified multilevel design enabling us to simultaneously examine these influences. We test hypotheses using a subsample of the European Social Survey (ESS), containing 19,878 first and second generation migrants. The analyses lead to three important conclusions. Firstly, disapproval of homosexuality is declining both over time and across cohorts. Secondly, migrants conform to levels of disapproval of homosexuality among natives in the destination country, and this explains the decline among migrants over time. Thirdly, religion has a multi-faceted influence on levels of disapproval of homosexuality among migrants. Copyright © 2014 Elsevier Inc. All rights reserved.

Ablation of the pro-apoptotic protein Bax protects mice from glucocorticoid-induced bone growth impairment.

PubMed

Zaman, Farasat; Chrysis, Dionisios; Huntjens, Kirsten; Fadeel, Bengt; Sävendahl, Lars

2012-01-01

Dexamethasone (Dexa) is a widely used glucocorticoid to treat inflammatory diseases; however, a multitude of undesired effects have been reported to arise from this treatment including osteoporosis, obesity, and in children decreased longitudinal bone growth. We and others have previously shown that glucocorticoids induce apoptosis in growth plate chondrocytes. Here, we hypothesized that Bax, a pro-apoptotic member of the Bcl-2 family, plays a key role in Dexa-induced chondrocyte apoptosis and bone growth impairment. Indeed, experiments in the human HCS-2/8 chondrocytic cell line demonstrated that silencing of Bax expression using small-interfering (si) RNA efficiently blocked Dexa-induced apoptosis. Furthermore, ablation of Bax in female mice protected against Dexa-induced bone growth impairment. Finally, Bax activation by Dexa was confirmed in human growth plate cartilage specimens cultured ex vivo. Our findings could therefore open the door for new therapeutic approaches to prevent glucocorticoid-induced bone growth impairment through specific targeting of Bax.

Contact toxicities of anuran skin alkaloids against the fire ant ( Solenopsis invicta)

NASA Astrophysics Data System (ADS)

Weldon, Paul J.; Cardoza, Yasmin J.; Vander Meer, Robert K.; Hoffmann, W. Clint; Daly, John W.; Spande, Thomas F.

2013-02-01

Nearly 500 alkaloids, representing over 20 structural classes, have been identified from the skin of neotropical poison frogs (Dendrobatidae). These cutaneous compounds, which are derived from arthropod prey of the frogs, generally are believed to deter predators. We tested the red imported fire ant ( Solenopsis invicta) for toxicosis following contact with 20 alkaloids (12 structural classes) identified from dendrobatids or other anurans. Individual ants forced to contact the dried residues of 13 compounds exhibited convulsions and/or reduced ambulation. We estimated the cutaneous concentrations of several compounds based on their reported recoveries from skin extracts of free-ranging frogs and our measurements of the skin surface areas of museum specimens. Pumiliotoxin 251D exhibited contact toxicity below its estimated cutaneous concentration in the Ecuadorian frog, Epipedobates anthonyi, an observation consistent with the hypothesized role of this compound in anuran chemical defense. Our results and those of a previous study of mosquitoes indicate that some anuran skin compounds function defensively as contact toxins against arthropods, permeating their exoskeleton.

Effective treatment of mitochondrial myopathy by nicotinamide riboside, a vitamin B3

PubMed Central

Khan, Nahid A; Auranen, Mari; Paetau, Ilse; Pirinen, Eija; Euro, Liliya; Forsström, Saara; Pasila, Lotta; Velagapudi, Vidya; Carroll, Christopher J; Auwerx, Johan; Suomalainen, Anu

2014-01-01

Nutrient availability is the major regulator of life and reproduction, and a complex cellular signaling network has evolved to adapt organisms to fasting. These sensor pathways monitor cellular energy metabolism, especially mitochondrial ATP production and NAD+/NADH ratio, as major signals for nutritional state. We hypothesized that these signals would be modified by mitochondrial respiratory chain disease, because of inefficient NADH utilization and ATP production. Oral administration of nicotinamide riboside (NR), a vitamin B3 and NAD+ precursor, was previously shown to boost NAD+ levels in mice and to induce mitochondrial biogenesis. Here, we treated mitochondrial myopathy mice with NR. This vitamin effectively delayed early- and late-stage disease progression, by robustly inducing mitochondrial biogenesis in skeletal muscle and brown adipose tissue, preventing mitochondrial ultrastructure abnormalities and mtDNA deletion formation. NR further stimulated mitochondrial unfolded protein response, suggesting its protective role in mitochondrial disease. These results indicate that NR and strategies boosting NAD+ levels are a promising treatment strategy for mitochondrial myopathy. PMID:24711540

Developmental and evolutionary novelty in the serrated teeth of theropod dinosaurs

PubMed Central

Brink, K. S.; Reisz, R. R.; LeBlanc, A. R. H.; Chang, R. S.; Lee, Y. C.; Chiang, C. C.; Huang, T.; Evans, D. C.

2015-01-01

Tooth morphology and development can provide valuable insights into the feeding behaviour and evolution of extinct organisms. The teeth of Theropoda, the only clade of predominantly predatory dinosaurs, are characterized by ziphodonty, the presence of serrations (denticles) on their cutting edges. Known today only in varanid lizards, ziphodonty is much more pervasive in the fossil record. Here we present the first model for the development of ziphodont teeth in theropods through histological, SEM, and SR-FTIR analyses, revealing that structures previously hypothesized to prevent tooth breakage instead first evolved to shape and maintain the characteristic denticles through the life of the tooth. We show that this novel complex of dental morphology and tissues characterizes Theropoda, with the exception of species with modified feeding behaviours, suggesting that these characters are important for facilitating the hypercarnivorous diet of most theropods. This adaptation may have played an important role in the initial radiation and subsequent success of theropods as terrestrial apex predators. PMID:26216577

Synthetic incoherent feedforward circuits show adaptation to the amount of their genetic template

PubMed Central

Bleris, Leonidas; Xie, Zhen; Glass, David; Adadey, Asa; Sontag, Eduardo; Benenson, Yaakov

2011-01-01

Natural and synthetic biological networks must function reliably in the face of fluctuating stoichiometry of their molecular components. These fluctuations are caused in part by changes in relative expression efficiency and the DNA template amount of the network-coding genes. Gene product levels could potentially be decoupled from these changes via built-in adaptation mechanisms, thereby boosting network reliability. Here, we show that a mechanism based on an incoherent feedforward motif enables adaptive gene expression in mammalian cells. We modeled, synthesized, and tested transcriptional and post-transcriptional incoherent loops and found that in all cases the gene product adapts to changes in DNA template abundance. We also observed that the post-transcriptional form results in superior adaptation behavior, higher absolute expression levels, and lower intrinsic fluctuations. Our results support a previously hypothesized endogenous role in gene dosage compensation for such motifs and suggest that their incorporation in synthetic networks will improve their robustness and reliability. PMID:21811230

Examining the relationship between childhood sexual abuse and borderline personality disorder: does social support matter?

PubMed

Elzy, Meredith B

2011-05-01

The relationship between childhood sexual abuse and borderline personality disorder is a prominent issue in the etiological research on borderline personality disorder. This study further explored the relationship between childhood sexual abuse and the development of borderline personality features while evaluating the moderating role of a primary social support source in a sample of 290 female undergraduate students enrolled at a major southeastern university. Consistent with previous research, retrospective self-reports of childhood sexual abuse and low social support were both positively correlated with current borderline personality features. It was hypothesized that the presence of a supportive relationship at the time the childhood sexual abuse occurred would moderate the relationship between childhood sexual abuse and borderline personality features. This moderation hypothesis was not supported in the current study, but post-hoc analyses reveal the need to further examine how we define social support following childhood sexual abuse. This research is a stepping stone toward the prevention of borderline personality disorder following childhood sexual abuse.

Chromosome 17: association of a large inversion polymorphism with corticosteroid response in asthma.

PubMed

Tantisira, Kelan G; Lazarus, Ross; Litonjua, Augusto A; Klanderman, Barbara; Weiss, Scott T

2008-08-01

A 900-kb inversion exists within a large region of conserved linkage disequilibrium (LD) on chromosome 17. CRHR1 is located within the inversion region and associated with inhaled corticosteroid response in asthma. We hypothesized that CRHR1 variants are in LD with the inversion, supporting a potential role for natural selection in the genetic response to corticosteroids. We genotyped six single nucleotide polymorphisms (SNPs) spanning chromosome 17: 40,410,565-42,372,240, including four SNPs defining inversion status. Similar allele frequencies and strong LD were noted between the inversion and a CRHR1 SNP previously associated with lung function response to inhaled corticosteroids. Each inversion-defining SNP was strongly associated with inhaled corticosteroid response in adult asthma (P values 0.002-0.005). The CRHR1 response to inhaled corticosteroids may thus be explained by natural selection resulting from inversion status or by long-range LD with another gene. Additional pharmacogenetic investigations into regions of chromosomal diversity, including copy number variation and inversions, are warranted.

Political complexity predicts the spread of ethnolinguistic groups

PubMed Central

Currie, Thomas E.; Mace, Ruth

2009-01-01

Human languages show a remarkable degree of variation in the area they cover. However, the factors governing the distribution of human cultural groups such as languages are not well understood. While previous studies have examined the role of a number of environmental variables the importance of cultural factors has not been systematically addressed. Here we use a geographical information system (GIS) to integrate information about languages with environmental, ecological, and ethnographic data to test a number of hypotheses that have been proposed to explain the global distribution of languages. We show that the degree of political complexity and type of subsistence strategy exhibited by societies are important predictors of the area covered by a language. Political complexity is also strongly associated with the latitudinal gradient in language area, whereas subsistence strategy is not. We argue that a process of cultural group selection favoring more complex societies may have been important in shaping the present-day global distribution of language diversity. PMID:19380740

Medical managers' managerial self-efficacy and role clarity: How do they bridge the budgetary participation-performance link?

PubMed

Macinati, Manuela S; Cantaluppi, Gabriele; Rizzo, Marco Giovanni

2017-02-01

This study explains the process ''how'' organizational accounting practices, such as budgetary participation, influence medical doctors' perceptions and beliefs associated with their hybrid role and what the consequences are on their performance. Building on social cognitive theory, we hypothesize a structural model in which managerial self-efficacy and role clarity mediate the effects of budgetary participation on performance. The data were collected by a survey conducted in an Italian hospital. The research hypotheses were tested employing a path model. The results suggest that role clarity and managerial self-efficacy fully mediate the link between budgetary participation and performance. From a managerial viewpoint results suggest that organizations that invest in budgetary participation will also affect individual beliefs about the perceived benefits of participation itself, since an information-rich internal environment allows employees to experience a clearer sense of direction through organizational goals. According to our results, organizations that seek self-directed employees should pay attention to the experience the medical managers acquire through budgetary participation. In fact, this event influences the employees' mental states-and specifically provides them with information needed to perform in the role and enhance their judgment of their own capabilities to organize and execute the required course of actions-which take on internal psychological motivation to reach performance levels.

The Effects of Psychotherapist's and Clients' Interpersonal Behaviors during a First Simulated Session: A Lab Study Investigating Client Satisfaction

PubMed Central

Moors, François; Zech, Emmanuelle

2017-01-01

The purpose of this study was to examine the effects of psychotherapists' behaviors during a first simulated therapy session on clients' satisfaction, including their intention to pursue or drop out from therapy. The importance of psychotherapists' warmth on clients' satisfaction was examined to check previous findings stressing this determining factor. Examining the role of warm behaviors is however insufficient according to the interpersonal perspective. We therefore tested the role of the psychotherapist's agentic behaviors since only a few studies provide contradictory results about the role of this interpersonal dimension on clients' satisfaction and how it is influenced by matching up client and therapist's profiles. To test our hypotheses and control for alternative therapy-related explanatory variables, we used different videos as experimental conditions manipulating the therapist's behaviors. Seventy-five participants had to imagine themselves as potential clients arriving for a first therapy session. They successively watched a role-playing therapist behaving according to five randomized interpersonal profiles. Results confirmed that warmth was a major dimension predicting client satisfaction. They revealed that agency was also a determinant of client satisfaction and that its effects depended on the client's own interpersonal agentic profile. Dominant clients were found to be more satisfied with the dominant psychotherapist than the submissive one while submissive clients preferred only the warm psychotherapist. These findings are discussed and suggest that therapists may need to be flexible and adapt their behaviors according to their client's interpersonal profile to increase their client satisfaction and decrease drop outs. PMID:29163262

Intrinsic motivation, performance, and the mediating role of mastery goal orientation: a test of self-determination theory.

PubMed

Cerasoli, Christopher P; Ford, Michael T

2014-01-01

Although intrinsic motivation has been linked repeatedly to performance and outcomes, the causal relationship between the two has remained unclear. To explain the link, this study considered the focusing influence of mastery goals. Using a three-wave panel study and hypotheses drawn from self-determination theory and achievement goal theory, the current study sought to clarify the relationships between intrinsic motivation, mastery goal orientation, and performance. Specifically, the current study hypothesized and found that mastery goals mediated (explained) the relationship between intrinsic motivation and performance.

The Empirical Testing of a Musical Performance Assessment Paradigm

ERIC Educational Resources Information Center

Russell, Brian E.

2010-01-01

The purpose of this study was to test a hypothesized model of aurally perceived performer-controlled musical factors that influence assessments of performance quality. Previous research studies on musical performance constructs, musical achievement, musical expression, and scale construction were examined to identify the factors that influence…

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.…

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…

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…

The Association between Violence Exposure and Aggression and Anxiety: The Role of Peer Relationships in Adaptation for Middle School Students

ERIC Educational Resources Information Center

Goodearl, Anna Ward; Salzinger, Suzanne; Rosario, Margaret

2014-01-01

This study examined how peer relationships contribute to young adolescents' adaptation in the face of exposure to community and family violence. It tested hypotheses about peers' role in processes relating exposure to behavioral and psychological outcomes, specifically, aggression and anxiety. Data were collected from 667 middle school students,…

Teachers' Level of Awareness of 21st Century Occupational Roles in Rivers State Secondary Schools

ERIC Educational Resources Information Center

Uche, Chineze M.; Kaegon, Leesi E. S. P.; Okata, Fanny Chiemezie

2016-01-01

This study investigated the teachers' level of awareness of 21st century occupational roles in Rivers state secondary schools. Three research questions and three hypotheses guided the study. The population of study comprised of 247 public secondary schools and 57 private secondary schools in Port Harcourt metropolis of Rivers state which gave a…

Embodiment in Communication--Aphasia, Apraxia and the Possible Role of Mirroring and Imitation

ERIC Educational Resources Information Center

Ahlsen, Elisabeth

2008-01-01

The role of embodiment in communication is attracting an increased interest. This interest is to some extent caused by hypotheses and findings concerning mirror neurons in macaques, that is, neurons that are activated by production as well as perception of, for example, a certain movement of action. Mirror neurons seem to provide a fairly simple…

Social Capital, Team Efficacy and Team Potency: The Mediating Role of Team Learning Behaviors

ERIC Educational Resources Information Center

van Emmerik, Hetty; Jawahar, I. M.; Schreurs, Bert; de Cuyper, Nele

2011-01-01

Purpose: Drawing on social capital theory and self-identification theory, this study aims to examine the associations of two indicators of social capital, personal networks and deep-level similarity, with team capability measures of team efficacy and team potency. The central focus of the study is to be the hypothesized mediating role of team…

The Role of Heavy Alcohol Use in the Developmental Process of Desistance in Dating Aggression during Adolescence

ERIC Educational Resources Information Center

Reyes, Heathe Luz McNaughton; Foshee, Vangie A.; Bauer, Daniel J.; Ennett, Susan T.

2011-01-01

The current study examined the role of heavy alcohol use in the developmental process of desistance in physical dating aggression during adolescence. Using longitudinal data spanning grades 8 through 12 we tested the hypotheses that (a) higher levels of early heavy alcohol use would be associated with decreased deceleration from dating aggression…

Macrophage Depletion Impairs Skeletal Muscle Regeneration: the Roles of Pro-fibrotic Factors, Inflammation, and Oxidative Stress.

PubMed

Xiao, Weihua; Liu, Yu; Chen, Peijie

2016-12-01

Muscle contusion is one of the most common muscle injuries in sports medicine. Macrophages play complex roles in the regeneration of skeletal muscle. However, the roles of macrophages, especially the mechanisms involved, in the regeneration of muscle contusion are still not fully understood. We hypothesize that the depletion of macrophages impairs skeletal muscle regeneration and that pro-fibrotic factors, inflammation, and oxidative stress may be involved in the process. To test these hypotheses, we constructed a muscle contusion injury and a macrophage depletion model and followed it up with morphological and gene expression analyses. The data showed that fibrotic scars were formed in the muscle of contusion injury, and they deteriorated in the mice of macrophage depletion. Furthermore, the sizes of regenerating myofibers were significantly reduced by macrophage depletion. Pro-fibrotic factors, inflammatory cytokines, chemokines, and oxidative stress-related enzymes increased significantly after muscle injury. Moreover, the expression of these factors was delayed by macrophage depletion. Most of them were still significantly higher in the later stage of regeneration. These results suggest that macrophage depletion impairs skeletal muscle regeneration and that pro-fibrotic factors, inflammation, and oxidative stress may play important roles in the process.

Individual Characteristics Influencing Physicians’ Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism

PubMed Central

Mazzetti, Greta; Biolcati, Roberta; Guglielmi, Dina; Vallesi, Caryn; Schaufeli, Wilmar B.

2016-01-01

The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands. PMID:27275828

Individual Characteristics Influencing Physicians' Perceptions of Job Demands and Control: The Role of Affectivity, Work Engagement and Workaholism.

PubMed

Mazzetti, Greta; Biolcati, Roberta; Guglielmi, Dina; Vallesi, Caryn; Schaufeli, Wilmar B

2016-06-06

The first purpose of the present study was to investigate the role of individual characteristics, i.e., positive and negative affectivity, in explaining the different perception of job control and job demands in a particularly demanding environment such as the healthcare setting. In addition, we aimed to explore the mediational role of work engagement and workaholism using the Job Demands-Resources Model as a theoretical framework. Data were collected using a sample of 269 Italian head physicians working in nine general hospitals. To test our hypotheses, the collected data were analyzed with structural equation modeling. Moreover, Sobel Test and bootstrapping were employed to assess the mediating hypotheses. Our results indicated that positive affectivity is related to work engagement, which, in its turn, showed a positive association with job control. In addition, workaholism mediated the relationship between negative affectivity and job demands. All in all, this study represents a first attempt to explore the role of trait affectivity as a dispositional characteristic able to foster the level of work engagement and workaholism exhibited by employees and, in turn, to increase the perceived levels of job control and job demands.

Molecular Genetic Analysis of Activation-tagged Transcription Factors Thought to be Involved in Photomorphogenesis

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

Neff, Michael

2011-06-23

Plants utilize light as a source of information via families of photoreceptors such as the red/far-red absorbing phytochromes (PHY) and the blue/UVA absorbing cryptochromes (CRY). The main goal of the Neff lab is to use molecular-genetic mutant screens to elucidate signaling components downstream of these photoreceptors. Activation-tagging mutagenesis led to the identification of two putative transcription factors that may be involved in both photomorphogenesis and hormone signaling pathways. sob1-D (suppressor of phyB-dominant) mutant phenotypes are caused by the over-expression of a Dof transcription factor previously named OBP3. Our previous studies indicate that OBP3 is a negative regulator of light-mediated cotyledonmore » expansion and may be involved in modulating responsiveness to the growth-regulating hormone auxin. The sob2-D mutant uncovers a role for LEP, a putative AP2/EREBP-like transcription factor, in seed germination, hypocotyl elongation and responsiveness to the hormone abscisic acid. Based on photobiological and genetic analysis of OBP3-knockdown and LEP-null mutations, we hypothesize that these transcription factors are involved in both light-mediated seedling development and hormone signaling. To examine the role that these genes play in photomorphogenesis we will: 1) Further explore the genetic role of OBP3 in cotyledon/leaf expansion and other photomorphogenic processes as well as examine potential physical interactions between OBP3 and CRY1 or other signaling components that genetically interact with this transcription factor 2) Test the hypothesis that OBP3 is genetically involved in auxin signaling and root development as well as examine the affects of this hormone and light on OBP3 protein accumulation. 3) Test the hypothesis that LEP is involved in seed germination, seedling photomorphogenesis and hormone signaling. Together these experiments will lead to a greater understanding of the complexity of interactions between photoreceptors and DNA-interacting proteins during photomorphogenesis. These studies also address the roles OBP3 and LEP may play as points of intersection between hormone signaling and photomorphogenesis. In the future, phenotypes caused by altered expression of these genes may generate useful traits for improving crop yield.« less

What to expect from an evolutionary hypothesis for a human disease: The case of type 2 diabetes.

PubMed

Watve, Milind; Diwekar-Joshi, Manawa

2016-10-01

Evolutionary medicine has a promise to bring in a conceptual revolution in medicine. However, as yet the field does not have the same theoretical rigour as that of many other fields in evolutionary studies. We discuss here with reference to type 2 diabetes mellitus (T2DM) what role an evolutionary hypothesis should play in the development of thinking in medicine. Starting with the thrifty gene hypothesis, evolutionary thinking in T2DM has undergone several transitions, modifications and refinements of the thrift family of hypotheses. In addition alternative hypotheses independent of thrift are also suggested. However, most hypotheses look at partial pictures; make selective use of supportive data ignoring inconvenient truths. Most hypotheses look at a superficial picture and avoid getting into the intricacies of underlying molecular, neuronal and physiological processes. Very few hypotheses have suggested clinical implications and none of them have been tested with randomized clinical trials. In the meanwhile the concepts in the pathophysiology of T2DM are undergoing radical changes and evolutionary hypotheses need to take them into account. We suggest an approach and a set of criteria to evaluate the relative merits of the alternative hypotheses. A number of hypotheses are likely to fail when critically evaluated against these criteria. It is possible that more than one selective process are at work in the evolution of propensity to T2DM, but the intercompatibility of the alternative selective forces and their relative contribution needs to be examined. The approach we describe could potentially lead to a sound evolutionary theory that is clinically useful and testable by randomized controlled clinical trials. Copyright © 2016 Elsevier GmbH. All rights reserved.

The Interaction between Semantic Representation and Episodic Memory.

PubMed

Fang, Jing; Rüther, Naima; Bellebaum, Christian; Wiskott, Laurenz; Cheng, Sen

2018-02-01

The experimental evidence on the interrelation between episodic memory and semantic memory is inconclusive. Are they independent systems, different aspects of a single system, or separate but strongly interacting systems? Here, we propose a computational role for the interaction between the semantic and episodic systems that might help resolve this debate. We hypothesize that episodic memories are represented as sequences of activation patterns. These patterns are the output of a semantic representational network that compresses the high-dimensional sensory input. We show quantitatively that the accuracy of episodic memory crucially depends on the quality of the semantic representation. We compare two types of semantic representations: appropriate representations, which means that the representation is used to store input sequences that are of the same type as those that it was trained on, and inappropriate representations, which means that stored inputs differ from the training data. Retrieval accuracy is higher for appropriate representations because the encoded sequences are less divergent than those encoded with inappropriate representations. Consistent with our model prediction, we found that human subjects remember some aspects of episodes significantly more accurately if they had previously been familiarized with the objects occurring in the episode, as compared to episodes involving unfamiliar objects. We thus conclude that the interaction with the semantic system plays an important role for episodic memory.

Pathological narcissism and acute anxiety symptoms after trauma: a study of Israeli civilians exposed to war.

PubMed

Besser, Avi; Zeigler-Hill, Virgil; Pincus, Aaron L; Neria, Yuval

2013-01-01

Diathesis-stress models of posttraumatic stress disorder (PTSD) hypothesize that exposure to trauma may interact with individual differences in the development of PTSD. Previous studies have not assessed immediate responses to a proximate stressor, but the current "natural laboratory" study was designed to empirically test the role that individual differences in pathological narcissism may play in the development of acute anxiety symptoms among civilians facing rocket and missile fire. We assessed demographic features, trauma exposure severity, narcissistic personality features, and acute anxiety symptoms (PTSD and General Anxiety Disorder [GAD]) among 342 Israeli female adults during the November 2012 eruption of violence in the Middle East. Results demonstrate an association between exposure severity and acute anxiety symptoms (both PTSD and GAD) for individuals with high levels of pathological narcissism but not for those with low levels of pathological narcissism. These results suggest that individuals with narcissistic personality features are at high risk for the development of acute anxiety symptoms following exposure to uncontrollable and life-threatening mass trauma. The findings underscore the role of intra-personal resources in the immediate psychological aftermath of war by highlighting the increased risk associated with narcissistic personality features. Theoretical and clinical implications of the findings are discussed.

The evolution of sex roles in mate searching.

PubMed

Fromhage, Lutz; Jennions, Michael; Kokko, Hanna

2016-03-01

Searching for mates is a critical stage in the life cycle of most internally, and many externally, fertilizing species. Males usually invest more in this costly activity than females, but the reasons for this are poorly understood. Previous models have shown that female-biased parental investment, including anisogamy, does not by itself select for male-biased mate searching, so it requires additional explanations. Here, we correct and expand upon earlier models, and present two novel hypotheses that might explain the evolution of male-biased mate searching. The "carry-over hypothesis" states that females benefit less from searching if the associated costs affect other stages of the life cycle, rather than arising only while searching. It is relevant to the evolution of morphological traits that improve searching efficiency but are also expressed in other contexts. The "mating window hypothesis" states that females benefit less from searching if their life cycle includes intervals during which the exact timing of mating does not matter for the appropriate timing of reproduction (e.g., due to sperm storage or delayed embryo implantation). Such intervals are more likely to exist for females given the general pattern of greater female parental investment. Our models shed new light on classic arguments about sex role evolution. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Self-concept deficits in massively multiplayer online role-playing games addiction.

PubMed

Leménager, Tagrid; Gwodz, Alexander; Richter, Anne; Reinhard, Iris; Kämmerer, Nina; Sell, Madlen; Mann, Karl

2013-01-01

Previous studies on Internet addiction point towards a particular constellation of personality traits and deficits in social competence of players addicted to massively multiplayer online role-playing games (MMORPGs), which are hypothesized to result from impairments in self-concept. The aim of this study was to examine differences in self-concept and degree of avatar identification in World of Warcraft addicted, non-addicted and naive (nonexperienced) participants. Participants (n = 45) completed interviews and self-report questionnaires on social, emotional and physical aspects of self-concept. Attributes of participants' 'actual self', 'ideal self' and their avatar were assessed using the Giessen test. The extent of avatar identification was examined by assessing differences between 'ideal self' and avatar evaluations. In contrast to nonaddicted and naive participants, addicted players showed a more negative body appraisal and lower self-esteem as well as lower permeability, social response, general mood and social potency on the Giessen test subscales. They further showed significantly lower discrepancies between 'ideal self' and avatar ratings on nearly all Giessen test subscales. The results point towards impairments in self-concept and a higher degree in avatar identification in addicted MMORPG players compared to the remaining participants. These results could have important implications for the treatment of addicted MMORPG players. Copyright © 2013 S. Karger AG, Basel.

Characterization of a venom gland-associated rhabdovirus in the parasitoid wasp Diachasmimorpha longicaudata.

PubMed

Simmonds, Tyler J; Carrillo, Daniel; Burke, Gaelen R

2016-01-01

Parasitoid wasps reproduce by laying their eggs on or inside of a host insect, which triggers a defense response in the host insect that kills the developing wasp. To counteract the host's lethal response, some parasitoid wasps are associated with symbiotic viruses that alter host metabolism and development to promote successful development of the wasp embryo. These symbiotic viruses display a number of characteristics that differ from those of pathogenic viruses, but are poorly understood with the exception of one group, the polydnaviruses. Here, we characterize the genome of a non-polydnavirus associated with parasitoid wasps, Diachasmimorpha longicaudata rhabdovirus (DlRhV), and assess its role as a potential mutualistic virus. Our results show that the DlRhV genome contains six open reading frames (ORFs). Three ORFs show sequence homology to known viral genes and one ORF encodes a previously identified protein, called parasitism-specific protein 24 (PSP24), that has been hypothesized to play a role in promoting successful parasitism by D. longicaudata. We constructed a phylogeny that shows that DlRhV is most closely related to other insect-infecting rhabdoviruses. Finally, we report that DlRhV infection does not occur in all populations of D. longicaudata, and is not required for successful parasitism. Copyright © 2016 Elsevier Ltd. All rights reserved.

Microgravity Induction of TRAIL Expression in Preosteoclast Cells Enhances Osteoclast Differentiation

NASA Astrophysics Data System (ADS)

Sambandam, Yuvaraj; Baird, Kelsey L.; Stroebel, Maxwell; Kowal, Emily; Balasubramanian, Sundaravadivel; Reddy, Sakamuri V.

2016-05-01

Evidence indicates that astronauts experience significant bone loss in space. We previously showed that simulated microgravity (μXg) using the NASA developed rotary cell culture system (RCCS) enhanced bone resorbing osteoclast (OCL) differentiation. However, the mechanism by which μXg increases OCL formation is unclear. RANK/RANKL signaling pathway is critical for OCL differentiation. Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) has been shown to increase osteoclastogenesis. We hypothesize that TRAIL may play an important role in μXg enhanced OCL differentiation. In this study, we identified by RT profiler PCR array screening that μXg induces high levels of TRAIL expression in murine preosteoclast cells in the absence of RANKL stimulation compared to ground based (Xg) cultures. We further identified that μXg elevated the adaptor protein TRAF-6 and fusion genes OC-STAMP and DC-STAMP expression in preosteoclast cells. Interestingly, neutralizing antibody against TRAIL significantly reduced μXg induced OCL formation. We further identified that over-expression of pTRAIL in RAW 264.7 cells enhanced OCL differentiation. These results indicate that TRAIL signaling plays an important role in the μXg increased OCL differentiation. Therefore, inhibition of TRAIL expression could be an effective countermeasure for μXg induced bone loss.

Comparative in vivo forefoot kinematics of Homo sapiens and Pan paniscus.

PubMed

Griffin, Nicole L; D'Août, Kristiaan; Richmond, Brian; Gordon, Adam; Aerts, Peter

2010-12-01

The human metatarsophalangeal joints play a key role in weight transmission and propulsion during bipedal gait, but at present, the identification of when a habitual, human-like metatarsi-fulcrimating mechanism first appeared in the fossil record is debated. Part of this debate can be attributed to the absence of certain detailed quantitative data distinguishing human and great ape forefoot form and function. The aim of this study is to quantitatively test previous observations that human metatarsophalangeal joints exhibit greater amounts of dorsal excursion (i.e., dorsiflexion) than those of Pan at the terminal stance phase of terrestrial locomotion. Video recordings were made in order to measure sagittal excursions of the medial metatarsophalangeal joints in habitually shod/unshod adult humans and adult bonobos (Pan paniscus). Results indicate that the human first and second metatarsophalangeal joints usually dorsiflex more than those of bonobos. When timing of maximum excursion of the first metatarsophalangeal joint is coupled with existing plantar pressure data, the unique role of the human forefoot as a key site of leverage and weight transmission is highlighted. These results support hypotheses that significant joint functional differences between great apes and humans during gait underlie taxonomic distinctions in trabecular bone architecture of the forefoot. Copyright © 2010 Elsevier Ltd. All rights reserved.

A systems biology approach to predict and characterize human gut microbial metabolites in colorectal cancer.

PubMed

Wang, QuanQiu; Li, Li; Xu, Rong

2018-04-18

Colorectal cancer (CRC) is the second leading cause of cancer-related deaths. It is estimated that about half the cases of CRC occurring today are preventable. Recent studies showed that human gut microbiota and their collective metabolic outputs play important roles in CRC. However, the mechanisms by which human gut microbial metabolites interact with host genetics in contributing CRC remain largely unknown. We hypothesize that computational approaches that integrate and analyze vast amounts of publicly available biomedical data have great potential in better understanding how human gut microbial metabolites are mechanistically involved in CRC. Leveraging vast amount of publicly available data, we developed a computational algorithm to predict human gut microbial metabolites for CRC. We validated the prediction algorithm by showing that previously known CRC-associated gut microbial metabolites ranked highly (mean ranking: top 10.52%; median ranking: 6.29%; p-value: 3.85E-16). Moreover, we identified new gut microbial metabolites likely associated with CRC. Through computational analysis, we propose potential roles for tartaric acid, the top one ranked metabolite, in CRC etiology. In summary, our data-driven computation-based study generated a large amount of associations that could serve as a starting point for further experiments to refute or validate these microbial metabolite associations in CRC cancer.

Role of F357 as an Oxygen Gate in the Oxidative Half-Reaction of Choline Oxidase.

PubMed

Salvi, Francesca; Rodriguez, Isela; Hamelberg, Donald; Gadda, Giovanni

2016-03-15

Choline oxidase from Arthrobacter globiformis catalyzes the oxidation of choline to glycine betaine by using oxygen as an electron acceptor. A partially rate limiting isomerization of the reduced wild-type enzyme during the reaction with oxygen was previously detected using solvent viscosity effects. In this study, we hypothesized that the side chains of M62 and F357, located at the entrance to the active site of choline oxidase, may be related to the slow isomerization detected. We engineered a double-variant enzyme M62A/F357A. The kinetic characterization of the double-variant enzyme showed a lack of the isomerization detected in wild-type choline oxidase, and a lack of saturation with an oxygen concentration as high as 1 mM, while most other kinetic parameters were similar to those of wild-type choline oxidase. The kinetic characterization of the single-variant enzymes established that only the side chain of F357 plays a role in the isomerization of choline oxidase in the oxidative half-reaction. Molecular dynamics studies suggest that the slow isomerization related to F357 is possibly due to the participation of the phenyl ring in a newly proposed gating mechanism for a narrow tunnel, assumed to regulate the access of oxygen to the reduced cofactor.

Prmt7 is dispensable in tissue culture models for adipogenic differentiation.

PubMed

Hu, Yu-Jie; Sif, Saïd; Imbalzano, Anthony N

2013-01-01

Protein arginine methylation is a common posttranslational modification that has been implicated in numerous biological processes including gene expression. The mammalian genome encodes nine protein arginine methyltransferases (Prmts) that catalyze monomethylation, asymmetric dimethylation, and symmetric dimethylation on arginine residues. Protein arginine methyltransferase 7 (Prmt7) is categorized as a type II and type III enzyme that produces symmetric dimethylated arginine and monomethylated arginine, respectively. However, the biological role of Prmt7 is not well characterized. We previously showed that Prmt5, a type II Prmt that associates with Brg1-based SWI/SNF chromatin remodeling complex, is required for adipocyte differentiation. Since Prmt7 also associates with Brg1-based SWI/SNF complex and modifies core histones, we hypothesized that Prmt7 might play a role in transcriptional regulation of adipogenesis. In the present study, we determined that the expression of Prmt7 did not change throughout adipogenic differentiation of C3H10T1/2 mesenchymal cells. Knockdown or over-expression of Prmt7 had no effect on lipid accumulation or adipogenic gene expression in differentiating C3H10T1/2 cells or in C/EBPα-reprogrammed NIH3T3 fibroblasts. Based on these results, we conclude that Prmt7, unlike Prmt5, is dispensable for adipogenic differentiation in tissue culture models.

Prmt7 is dispensable in tissue culture models for adipogenic differentiation

PubMed Central

Imbalzano, Anthony N.

2013-01-01

Protein arginine methylation is a common posttranslational modification that has been implicated in numerous biological processes including gene expression. The mammalian genome encodes nine protein arginine methyltransferases (Prmts) that catalyze monomethylation, asymmetric dimethylation, and symmetric dimethylation on arginine residues. Protein arginine methyltransferase 7 (Prmt7) is categorized as a type II and type III enzyme that produces symmetric dimethylated arginine and monomethylated arginine, respectively. However, the biological role of Prmt7 is not well characterized. We previously showed that Prmt5, a type II Prmt that associates with Brg1-based SWI/SNF chromatin remodeling complex, is required for adipocyte differentiation. Since Prmt7 also associates with Brg1-based SWI/SNF complex and modifies core histones, we hypothesized that Prmt7 might play a role in transcriptional regulation of adipogenesis. In the present study, we determined that the expression of Prmt7 did not change throughout adipogenic differentiation of C3H10T1/2 mesenchymal cells. Knockdown or over-expression of Prmt7 had no effect on lipid accumulation or adipogenic gene expression in differentiating C3H10T1/2 cells or in C/EBPα-reprogrammed NIH3T3 fibroblasts. Based on these results, we conclude that Prmt7, unlike Prmt5, is dispensable for adipogenic differentiation in tissue culture models. PMID:24715966

Unleashing creativity: The role of left temporoparietal regions in evaluating and inhibiting the generation of creative ideas.

PubMed

Mayseless, Naama; Aharon-Peretz, Judith; Shamay-Tsoory, Simone

2014-11-01

Human creativity is thought to entail two processes. One is idea generation, whereby ideas emerge in an associative manner, and the other is idea evaluation, whereby generated ideas are evaluated and screened. Thus far, neuroimaging studies have identified several brain regions as being involved in creativity, yet only a handful of studies have examined the neural basis underlying these two processes. We found that an individual with left temporoparietal hemorrhage who had no previous experience as an artist developed remarkable artistic creativity, which diminished as the hemorrhage receded. We thus hypothesized that damage to the evaluation network of creativity during the initial hematoma had a releasing effect on creativity by "freeing" the idea generation system. In line with this hypothesis, we conducted a subsequent fMRI study showing that decreased left temporal and parietal activations among healthy individuals as they evaluated creative ideas selectively predicted higher creativity. The current studies provide converging multi-method evidence suggesting that the left temporoparietal area is part of a neural network involved in evaluating creativity, and that as such may act as inhibitors of creativity. We propose an explanatory model of creativity centered upon the key role of the left temporoparietal regions in evaluating and inhibiting creativity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Problems with non-adherence to antipsychotic medication in Samoan new Zealanders: A literature review

PubMed Central

Ioasa-Martin, Itagia; Moore, Laurie Jo

2012-01-01

This paper explores what is known about adherence to antipsychotic medications in general and the possible reasons for non-adherence in Samoan New Zealanders. Samoan New Zealanders are either Samoan-born immigrants or their descendents born in New Zealand. Clinicians recognize a high prevalence of non-adherence among Samoan New Zealanders. The authors hypothesize that traditional Samoan beliefs play a prominent role in problems with adherence. To investigate this hypothesis, a review of the literature on adherence in Samoan New Zealanders was undertaken. Documents from the Ministry of Health support the hypothesis. To investigate this issue, the Ministry of Health initiated a qualitative research project to examine the nature of Samoan traditional beliefs. The results of this study are summarized. No research had previously been undertaken on adherence in Samoan New Zealanders. In general, there is a lack of research on all aspects of the mental health of Pacific peoples in New Zealand. Literature reviews of adherence research consistently show that interventions that improve adherence address the beliefs, behaviours, and relationships surrounding adherence. This finding supports the author's hypothesis that traditional beliefs play an important role in the problem of adherence. Further definitive study with Samoan New Zealanders is required. PMID:22417230

The Screaming Boredom of Learning Science

ERIC Educational Resources Information Center

Krips, H.

1977-01-01

Advocates changing the role of secondary school science from one of theory verification and problem solving to the formulation and acceptance of hypotheses for observed phenomena. Provides an example of the procedure using Hooke's Law. (CP)

Marital role attitudes and expected role behaviors of college youth in mainland China and Taiwan.

PubMed

Hsieh, K H; Burgess, R L

1994-09-01

Mainland China and Taiwan have been politically and physically segregated since 1949, and it was not until the late 1980s that limited contacts and cultural exchanges between the two societies began to take place. During their period of segregation, the two societies adopted different approaches toward gender roles. While gender equality was actively promoted in mainland China, the government in Taiwan lacked the theoretical guidance on how to achieve such equality. Gender egalitarianism in Taiwan therefore remains at the abstract or philosophical level with no specification of what gender equality means in concrete terms. Testing the hypothesis that people in mainland China have become more egalitarian than have people in Taiwan with respect to the division of marital roles, the authors investigated the differences in marital role attitudes and expected behavior among selected college students in mainland China and Taiwan. Survey responses were obtained from 185 male and 154 female students from Taiwan and 150 male and 138 female students from mainland China of different years and majors on four dimensions of marital role attitudes and six areas of traditional husband and wife role behaviors. The dimensions were determined through exploratory and confirmatory factor analyses. The data indicate that although most of the hypothesized societal differences are supported, some are not. The authors speculate that possible regressive changes in mainland China and progressive changes in Taiwan during the past decade were responsible for the discrepancy between hypotheses and results.

In vivo and in vitro response to octreotide LAR in a TSH-secreting adenoma: characterization of somatostatin receptor expression and role of subtype 5.

PubMed

Gatto, Federico; Barbieri, Federica; Castelletti, Lara; Arvigo, Marica; Pattarozzi, Alessandra; Annunziata, Francesca; Saveanu, Alexandru; Minuto, Francesco; Castellan, Lucio; Zona, Gianluigi; Florio, Tullio; Ferone, Diego

2011-06-01

Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism and account for less than 2% of pituitary adenomas. Medical therapy with somatostatin analogues (SSAs) effectively reduces TSH secretion in approximately 80% of patients and induces shrinkage in about 45% of tumors. According with previous data, resistance to SSA treatment might be due to heterogeneity in somatostatin receptors (SSTRs) expression. We report the case of TSHoma in a 41-year-old man treated with octreotide LAR that caused a dramatic decrease of TSH and thyroid hormones and tumor shrinkage already after 3 months of pre-surgical therapy. In search of potential molecular determinants of octreotide effectiveness, we measured, in primary cultures from this tumor, SSTR and dopamine D2 receptor (D2R) expression, and octreotide and/or cabergoline effects on TSH secretion and cell proliferation. SSTR5 and D2R expression was higher than SSTR2. Octreotide significantly inhibited TSH secretion more effectively than cabergoline (P<0.001), whereas the combined treatment was comparable with cabergoline alone. Similarly, octreotide resulted more effective than cabergoline on cell proliferation, while the combination did not show any additive or synergistic effects. In conclusion, the significant antisecretive and antiproliferative effect of octreotide in this patient might be related to the high expression of SSTR5, in the presence of SSTR2. After reviewing the literature, indeed, in line with previous observations, we hypothesize that SSTR5/SSTR2 ratio in TSHomas may represent a useful marker in predicting the outcome of therapy with SSAs. The role of D2R should be further explored considering that the presence of D2R can influence SSTRs functionality. © Springer Science+Business Media, LLC 2010

Calcium sensitization in human esophageal muscle: role for RhoA kinase in maintenance of lower esophageal sphincter tone.

PubMed

Sims, Stephen M; Chrones, Tom; Preiksaitis, Harold G

2008-10-01

A rise in intracellular-free calcium ([Ca(2+)](i)) concentration is important for initiating contraction of smooth muscles, and Ca(2+) sensitization involving RhoA kinase can sustain tension. We previously found that [Ca(2+)](i) was comparable in cells from the esophageal body (EB) and lower esophageal sphincter (LES) muscles, despite the fact that the LES maintains resting tone. We hypothesized that Ca(2+) sensitization contributes to contraction in human esophageal muscle. Tension and [Ca(2+)](i) were measured simultaneously in intact human EB and LES muscles using the ratiometric Ca(2+)-sensitive dye fura-2. Spontaneous oscillations in EB muscle tension were associated with transient elevations of [Ca(2+)](i). Carbachol caused a large increase in tension, compared with spontaneous oscillations, although the rise of [Ca(2+)](i) was similar, suggesting Ca(2+) sensitization. The RhoA-kinase blockers (R)-(+)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate (Y-27632) and 1-(5-isoquinolinesulfonyl)-homopiperazine hydrochloride (HA-1077) reduced carbachol- and nerve-evoked contraction of the EB, accompanied by smaller reduction in the rise of [Ca(2+)](i). Protein kinase C inhibitors reduced force to a lesser extent. RhoA-kinase blockers caused concentration-dependent reduction of tension in spontaneously contracted LES muscles. Moreover, RhoA-kinase blockers reduced intrinsic nerve-evoked and carbachol-evoked contraction. However, there was no effect on nerve- or nitric oxide-mediated relaxation of LES. Ca(2+) sensitization mediated by the RhoA-kinase pathway has an important role in contraction of human EB muscles and LES tonic contraction, a feature not previously recognized.

Sucrose Transporter ZmSut1 Expression and Localization Uncover New Insights into Sucrose Phloem Loading1[OPEN

PubMed Central

Baker, R. Frank; Leach, Kristen A.; Boyer, Nathanial R.; Skopelitis, Tara; Jackson, David; Braun, David M.

2016-01-01

Sucrose transporters (SUTs) translocate sucrose (Suc) across cellular membranes, and in eudicots, multiple SUTs are known to function in Suc phloem loading in leaves. In maize (Zea mays), the Sucrose Transporter1 (ZmSut1) gene has been implicated in Suc phloem loading based upon RNA expression in leaves, electrophysiological experiments, and phenotypic analysis of zmsut1 mutant plants. However, no previous studies have examined the cellular expression of ZmSut1 RNA or the subcellular localization of the ZmSUT1 protein to assess the gene’s hypothesized function in Suc phloem loading or to evaluate its potential roles, such as phloem unloading, in nonphotosynthetic tissues. To this end, we performed RNA in situ hybridization experiments, promoter-reporter gene analyses, and ZmSUT1 localization studies to elucidate the cellular expression pattern of the ZmSut1 transcript and protein. These data showed that ZmSut1 was expressed in multiple cell types throughout the plant and indicated that it functions in phloem companion cells to load Suc and also in other cell types to retrieve Suc from the apoplasm to prevent its accumulation and loss to the transpiration stream. Additionally, by comparing a phloem-mobile tracer with ZmSut1 expression, we determined that developing maize leaves dynamically switch from symplasmic to apoplasmic phloem unloading, reconciling previously conflicting reports, and suggest that ZmSut1 does not have an apparent function in either unloading process. A model for the dual roles for ZmSut1 function (phloem loading and apoplasmic recycling), Sut1 evolution, and its possible use to enhance Suc export from leaves in engineering C3 grasses for C4 photosynthesis is discussed. PMID:27621426

Inhibition of IKKβ Reduces Ethanol Consumption in C57BL/6J Mice.

PubMed

Truitt, Jay M; Blednov, Yuri A; Benavidez, Jillian M; Black, Mendy; Ponomareva, Olga; Law, Jade; Merriman, Morgan; Horani, Sami; Jameson, Kelly; Lasek, Amy W; Harris, R Adron; Mayfield, R Dayne

2016-01-01

Proinflammatory pathways in neuronal and non-neuronal cells are implicated in the acute and chronic effects of alcohol exposure in animal models and humans. The nuclear factor-κB (NF-κB) family of DNA transcription factors plays important roles in inflammatory diseases. The kinase IKKβ mediates the phosphorylation and subsequent proteasomal degradation of cytosolic protein inhibitors of NF-κB, leading to activation of NF-κB. The role of IKKβ as a potential regulator of excessive alcohol drinking had not previously been investigated. Based on previous findings that the overactivation of innate immune/inflammatory signaling promotes ethanol consumption, we hypothesized that inhibiting IKKβ would limit/decrease drinking by preventing the activation of NF-κB. We studied the systemic effects of two pharmacological inhibitors of IKKβ, TPCA-1 and sulfasalazine, on ethanol intake using continuous- and limited-access, two-bottle choice drinking tests in C57BL/6J mice. In both tests, TPCA-1 and sulfasalazine reduced ethanol intake and preference without changing total fluid intake or sweet taste preference. A virus expressing Cre recombinase was injected into the nucleus accumbens and central amygdala to selectively knock down IKKβ in mice genetically engineered with a conditional Ikkb deletion ( Ikkb F/F ). Although IKKβ was inhibited to some extent in astrocytes and microglia, neurons were a primary cellular target. Deletion of IKKβ in either brain region reduced ethanol intake and preference in the continuous access two-bottle choice test without altering the preference for sucrose. Pharmacological and genetic inhibition of IKKβ decreased voluntary ethanol consumption, providing initial support for IKKβ as a potential therapeutic target for alcohol abuse.

Analysis of the LIV System of Campylobacter jejuni Reveals Alternative Roles for LivJ and LivK in Commensalism beyond Branched-Chain Amino Acid Transport ▿

PubMed Central

Ribardo, Deborah A.; Hendrixson, David R.

2011-01-01

Campylobacter jejuni is a leading cause of diarrheal disease in humans and an intestinal commensal in poultry and other agriculturally important animals. These zoonotic infections result in significant amounts of C. jejuni present in the food supply to contribute to disease in humans. We previously found that a transposon insertion in Cjj81176_1038, encoding a homolog of the Escherichia coli LivJ periplasmic binding protein of the leucine, isoleucine, and valine (LIV) branched-chain amino acid transport system, reduced the commensal colonization capacity of C. jejuni 81-176 in chicks. Cjj81176_1038 is the first gene of a six-gene locus that encodes homologous components of the E. coli LIV system. By analyzing mutants with in-frame deletions of individual genes or pairs of genes, we found that this system constitutes a LIV transport system in C. jejuni responsible for a high level of leucine acquisition and, to a lesser extent, isoleucine and valine acquisition. Despite each LIV protein being required for branched-chain amino acid transport, only the LivJ and LivK periplasmic binding proteins were required for wild-type levels of commensal colonization of chicks. All LIV permease and ATPase components were dispensable for in vivo growth. These results suggest that the biological functions of LivJ and LivK for colonization are more complex than previously hypothesized and extend beyond a role for binding and acquiring branched-chain amino acids during commensalism. In contrast to other studies indicating a requirement and utilization of other specific amino acids for colonization, acquisition of branched-chain amino acids does not appear to be a determinant for C. jejuni during commensalism. PMID:21949065

Who's Got the Booze? The Role of Access to Alcohol in the Relations Between Social Status and Individual Use.

PubMed

Deutsch, Arielle R; Steinley, Douglas; Sher, Kenneth J; Slutske, Wendy S

2017-09-01

The findings of previous research that examined relationships between popularity and alcohol use in adolescents have been mixed, and few hypotheses have proposed mechanisms for this relationship. The current study expands on previous literature (a) by examining a possible mechanism that can explain the relation between popularity and alcohol use (home access to alcohol) and (b) by using another sociometric measure ("betweenness"), beyond popularity, that may relate more to home alcohol access. Using network-level data from adolescents in 9th-11th grades in eight schools within two in-home waves of the National Longitudinal Study of Adolescent to Adult Health (Add Health), we examined two sociometric measures of social status: popularity (number of schoolmates who nominated participants as a friend) and betweenness (level of ties participants have to multiple social subgroups within a network). Betweenness, but not popularity, related to later alcohol use. Having home access to alcohol positively related to later alcohol use, and having friends with home access to alcohol negatively related to later alcohol use. Alcohol access was also related to later sociometric status. Friends' alcohol access negatively related to later betweenness, and personal alcohol access moderated other pathways predicting betweenness. Betweenness appears to play a unique role in the association between social status and alcohol use in adolescent social networks. This is potentially tied to specific ways in which adolescents may be able to access alcohol (through home or through friends with access at home). More research is necessary to examine the ways in which multiple sociometric statuses relate to the contexts in which adolescents access and use alcohol.

The role of impoundments in the sediment budget of the conterminous United States

USGS Publications Warehouse

Renwick, W.H.; Smith, S.V.; Bartley, J.D.; Buddemeier, R.W.

2005-01-01

Previous work on sediment budgets for U.S. agricultural regions has concluded that most sediment derived from accelerated erosion is still on the landscape, primarily in colluvial and alluvial deposits. Here we examine the role of small impoundments in the subcontinental sediment budget. A recent inventory based on a 30-m satellite imagery reveals approximately 2.6 million ponds, while extrapolation from a sample of 1:24,000 topographic quadrangles suggests the total may be as large as 8-9 million. These ponds capture an estimated 21% of the total drainage area of the conterminous U.S., representing 25% of total sheet and rill erosion. We estimate the total sedimentation in these small impoundments using three different methods; these estimates range from 0.43 to 1.78 ?? 109 m3 yr-1. Total sedimentation in ???43,000 reservoirs from the National Inventory of Dams is estimated at 1.67 ?? 109 m3 yr-1. Total USLE erosion in 1992 was 2.4 ?? 109 m3 yr-1, and export to coastal areas is estimated at 0.6 ?? 109 m3 yr-1. Total sedimentation in impoundments is large in relation to upland erosion, in apparent contradiction to previous studies that have identified colluvial and alluvial deposition as the primary sinks. Several alternative hypotheses that could help explain this result are proposed. Regardless of which of these alternatives may prove to be the most significant in any given setting, it is clear that most sedimentation is now taking place in subaqueous rather than subaerial environments, and that small impoundments are a major sediment sink. ?? 2005 Elsevier B.V. All rights reserved.

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…

A Validation Study of Student Differentiation between Computing Disciplines

ERIC Educational Resources Information Center

Battig, Michael; Shariq, Muhammad

2011-01-01

Using a previously published study of how students differentiate between computing disciplines, this study attempts to validate the original research and add additional hypotheses regarding the type of institution that the student resides. Using the identical survey instrument from the original study, students in smaller colleges and in different…