scholarly journals What ecological factors favor parthenogenesis over sexual reproduction? A study on the facultatively parthenogenetic mayfly Alainites muticus in natural populations.

2021 ◽  
Author(s):  
Maud Liegeois ◽  
Michel Sartori ◽  
Tanja Schwander
Keyword(s):  
Structural Equation ◽  
Sex Ratios ◽  
Natural Populations ◽  
Ecological Factors ◽  
Biotic Interactions ◽  
Community Diversity ◽  
Equation Modeling ◽  
Reproductive Assurance ◽  
Adult Lifespan ◽  
Mate Limitation

Different reproductive modes are characterized by costs and benefits which often depend on ecological contexts. Benefits of sex are expected to increase under complex biotic interactions, whereas parthenogenesis can be beneficial for reproductive assurance when females are mate limited. Here, we study how different ecological contexts influence the frequency of sex or parthenogenesis in the facultatively parthenogenetic mayfly Alainites muticus. We first verified that high parthenogenetic frequencies translate into female-biased population sex ratios. We then measured the population sex ratio (a proxy for parthenogenetic capacities), density of individuals (mate limitation) and community diversity (biotic interaction complexity) for 159 A. muticus populations, and used structural equation modeling to investigate their direct and indirect influences on sex ratios. We found no effect of community diversity or altitude on sex ratios. Furthermore, even when females can reproduce parthenogenetically, they generally reproduce sexually, indicating that the benefits of sex exceed its costs in most situations. Sex ratios become female-biased in low population densities, as expected if mate limitation selects for parthenogenesis. Mate limitation might be widespread in mayflies because of their very short adult lifespan and limited dispersal, which can generate strong selection for reproductive assurance and may provide a steppingstone towards obligate parthenogenesis.

Correlated personality change across time and age

2021 ◽  
pp. 089020702110140
Author(s):  
Gabriel Olaru ◽  
Mathias Allemand
Keyword(s):  
Structural Equation ◽  
Rank Order ◽  
Personality Development ◽  
The United States ◽  
Change Score ◽  
Personality Change ◽  
Equation Modeling ◽  
Model Parameters ◽  
Cross Sectional ◽  
Adult Lifespan

The goal of this study was to examine differential and correlated change in personality across the adult lifespan. Studying differential and correlated change can help understand whether intraindividual trait change trajectories deviate from the norm and how these trajectories are coupled with each other. We used data from two large longitudinal panel studies from the United States that covered a total age range of 20 to 95 years on the first measurement occasion. We used correlated factor models and bivariate latent change score models to examine the rank-order stability and correlations between change across three measurement waves covering 18 years ( N = 3250) and four measurement waves covering 12 years ( N = 4145). We examined the moderation effects of continuous age on these model parameters using local structural equation modeling. The results suggest that the test–retest correlations decrease with increasing time between measurements but are unaffected by participants’ age. We found that change processes in Extraversion, Openness, Agreeableness, and Conscientiousness were strongly related, particularly in late adulthood. Correlated change patterns were highly stable across time intervals and similar to the initial cross-sectional Big Five correlations. We discuss potential mechanisms and implications for personality development research.

Age-Related Effects on Interoceptive Accuracy, General Interoceptive Sensibility, and Specific Interoceptive Sensibility

2020 ◽  
Vol 27 (4) ◽  
pp. 154-170 ◽  
Author(s):  
L. Nusser ◽  
O. Pollatos ◽  
D. Zimprich
Keyword(s):  
Structural Equation ◽  
Empirical Support ◽  
Self Report ◽  
Three Dimensions ◽  
Equation Modeling ◽  
Adult Lifespan ◽  
Age Related ◽  
Physical Diseases ◽  
Interoceptive Accuracy ◽  
Subjective Belief

Abstract. Background: The current research into interoception distinguishes between interoceptive accuracy (IAcc), the accurate detection of internal sensations (e.g., heartbeats) as measured by performance on objective IAcc tasks, and interoceptive sensibility (IS), the subjective belief concerning one’s own experience of internal sensations as measured either through self-report questionnaires or through one’s confidence in the accuracy during an IAcc task. Aims: As the two measures of IS, however, are usually uncorrelated and show differential relationships to IAcc, we suggest different types of IS, a general IS and a specific IS. Further, based on a growing body of research linking IAcc and IS to physical and mental diseases, the development of interoception across the adult lifespan is of importance. Methods: Using Structural Equation Modeling the present paper investigates the relationships among IAcc assessed by a heartbeat counting task, and the two proposed dimensions of IS in 138 participants ( Mage = 42.67, SDage = 18.77). Furthermore, we examine age-related differences in IAcc, as well as in general and specific IS. Results: In terms of the relationship between the three dimensions, general and specific IS were weakly correlated and exhibited different relationships to IAcc. Further, we found different age effects on the three interoceptive dimensions. Whereas IAcc decreased with age, specific IS tend to increase with age, and general IS remained unaffected by age. Conclusion: The findings provide further empirical support for a dissociation between general and specific IS and raised important questions concerning the relation between interoceptive accuracy and the emergence of physical diseases in older age.

scholarly journals Age differentiation within grey matter, white matter and between memory and white matter in an adult lifespan cohort

2017 ◽  
Author(s):  
Susanne M. M. de Mooij ◽  
Richard N. A. Henson ◽  
Lourens J. Waldorp ◽  
Cam-CAN ◽  
Rogier A. Kievit
Keyword(s):  
White Matter ◽  
Cognitive Functions ◽  
Structural Equation ◽  
Grey Matter ◽  
Fluid Intelligence ◽  
Cognitive Factors ◽  
Equation Modeling ◽  
Grey Matter Volume ◽  
Adult Lifespan ◽  
Age Related

AbstractIt is well-established that brain structures and cognitive functions change across the lifespan. A longstanding hypothesis called age differentiation additionally posits that the relations between cognitive functions also change with age. To date however, evidence for age-related differentiation is mixed, and no study has examined differentiation of the relationship between brain and cognition. Here we use multi-group Structural Equation Modeling and SEM Trees to study differences within and between brain and cognition across the adult lifespan (18-88 years) in a large (N>646, closely matched across sexes), population-derived sample of healthy human adults from the Cambridge Centre for Ageing and Neuroscience (www.cam-can.org). After factor analyses of grey-matter volume (from T1- and T2-weighted MRI) and white-matter organisation (fractional anisotropy from Diffusion-weighted MRI), we found evidence for differentiation of grey and white matter, such that the covariance between brain factors decreased with age. However, we found no evidence for age differentiation between fluid intelligence, language and memory, suggesting a relatively stable covariance pattern between cognitive factors. Finally, we observed a specific pattern of age differentiation between brain and cognitive factors, such that a white matter factor, which loaded most strongly on the hippocampal cingulum, became less correlated with memory performance in later life. These patterns are compatible with reorganization of cognitive functions in the face of neural decline, and/or with the emergence of specific subpopulations in old age.Significance statementThe theory of age differentiation posits age-related changes in the relationships between cognitive domains, either weakening (differentiation) or strengthening (de-differentiation), but evidence for this hypothesis is mixed. Using age-varying covariance models in a large cross-sectional adult lifespan sample, we found age-related reductions in the covariance among both brain measures (neural differentiation), but no covariance change between cognitive factors of fluid intelligence, language and memory. We also observed evidence of uncoupling (differentiation) between a white matter factor and cognitive factors in older age, most strongly for memory. Together, our findings support age-related differentiation as a complex, multifaceted pattern that differs for brain and cognition, and discuss several mechanisms that might explain the changing relationship between brain and cognition.

scholarly journals Mediating processes in the relations of parental monitoring and school climate with cyberbullying: The role of moral disengagement

2019 ◽  
Vol 15 (3) ◽  
pp. 568-594 ◽  
Author(s):  
Maria Giuseppina Bartolo ◽  
Anna Lisa Palermiti ◽  
Rocco Servidio ◽  
Pasquale Musso ◽  
Angela Costabile
Keyword(s):  
School Climate ◽  
Parental Monitoring ◽  
Structural Equation ◽  
Moral Disengagement ◽  
Ecological Factors ◽  
Equation Modeling ◽  
Environmental Predictors ◽  
Collaborative Strategies ◽  
Mediating Mechanisms

In recent years, studies have extensively explored both personal and environmental predictors of cyberbullying. Among these predictors, parental monitoring and school climate were often expected to be associated with cyberbullying behaviors. However, little is known about the mediating mechanisms through which these relations may develop. The present study aimed to expand the current research by testing a theoretical model including the mediating role of moral disengagement in the relations between parental monitoring (including less collaborative vs. more collaborative strategies), school climate, and cyberbullying behaviors. Five hundred and seventy-one Italian adolescents (54.5% male) aged 14 to 20 years were recruited from high schools. Measures included demographics and parental monitoring, school climate, moral disengagement and cyberbullying scales. To test the hypothesized model, we estimated full and partial mediation models by structural equation modeling. Results showed negative indirect links of parental monitoring (but only the more collaborative strategies) and school climate with cyberbullying via moral disengagement. Less collaborative strategies of parental monitoring were neither directly nor indirectly related to cyberbullying. The findings revealed moral disengagement as an important process in explaining how ecological factors, such as parenting behaviors and school environments, are associate with cyberbullying. Limitations, strengths, and implications for practice are presented.

scholarly journals Abiotic factors influence patterns of bacterial diversity and community composition in the Dry Valleys of Antarctica

2020 ◽  
Vol 96 (5) ◽  
Author(s):  
Eric M Bottos ◽  
Daniel C Laughlin ◽  
Craig W Herbold ◽  
Charles K Lee ◽  
Ian R McDonald ◽  
...  
Keyword(s):  
Community Composition ◽  
Bacterial Communities ◽  
Structural Equation ◽  
Abiotic Factors ◽  
Biotic Interactions ◽  
Equation Modeling ◽  
Dry Valleys ◽  
Physicochemical Variables ◽  
Soil Conductivity ◽  
Community Dissimilarity

ABSTRACT The Dry Valleys of Antarctica are a unique ecosystem of simple trophic structure, where the abiotic factors that influence soil bacterial communities can be resolved in the absence of extensive biotic interactions. This study evaluated the degree to which aspects of topographic, physicochemical and spatial variation explain patterns of bacterial richness and community composition in 471 soil samples collected across a 220 square kilometer landscape in Southern Victoria Land. Richness was most strongly influenced by physicochemical soil properties, particularly soil conductivity, though significant trends with several topographic and spatial variables were also observed. Structural equation modeling (SEM) supported a final model in which variation in community composition was best explained by physicochemical variables, particularly soil water content, and where the effects of topographic variation were largely mediated through their influence on physicochemical variables. Community dissimilarity increased with distance between samples, and though most of this variation was explained by topographic and physicochemical variation, a small but significant relationship remained after controlling for this environmental variation. As the largest survey of terrestrial bacterial communities of Antarctica completed to date, this work provides fundamental knowledge of the Dry Valleys ecosystem, and has implications globally for understanding environmental factors that influence bacterial distributions.

scholarly journals Phylogeography needs extrinsic causal theory

2020 ◽  
Author(s):  
Greer Dolby
Keyword(s):  
Structural Equation Modeling ◽  
Structural Equation ◽  
Biotic Interactions ◽  
Directed Acyclic Graphs ◽  
Interdisciplinary Studies ◽  
Equation Modeling ◽  
Natural Systems ◽  
Geological Processes ◽  
The Earth ◽  
Causal Structures

The overarching goal of phylogeography and the Earth-life sciences is to understand how geological and climatic processes contribute to the generation and distribution of the diversity of life on Earth. This question, at its heart, is one of causation. Causal structures are used to explain the cause-effect relations within natural systems and can be quantitatively evaluated through structural equation modeling. Here, I suggest that causality provides an organizing framework for linking extrinsic (geological) processes with genetic diversification and species richness that can be broadly applied. By using causal structures within individualistic taxonomic and geographic studies, we can tackle higher-order questions to reveal how Earth shapes life through time. Causal diagrams and structural equation modeling allow the abstraction of variables to accommodate (1) the heterogeneity of individual study systems, and (2) the need to reduce the complexity in interdisciplinary studies. Using directed acyclic graphs to articulate these relationships yield actionable hypotheses that feed directly back into Earth-life theory. I suggest many classically studied features, such as mountain ranges, are aggregate features whose causal effects can be decomposed into networks of indirect causal paths that are empirically testable. Formalizing causal relationships mitigates against the risk of mis-assigning causality, which can cloud our understanding of how the Earth-life system functions. Finally, this approach formalizes a way to test ideas about the top-down causation of biodiversity. Knowing how much of life is extrinsically forced would in turn reveal the importance of biotic-biotic interactions as well as intrinsic organismal and stochastic effects in shaping the diversity we see today.

scholarly journals Mediating processes in the relations of parental monitoring and school climate with cyberbullying: The role of moral disengagement

2019 ◽  
Vol 15 (3) ◽  
pp. 568-594
Author(s):  
Maria Giuseppina Bartolo ◽  
Anna Lisa Palermiti ◽  
Rocco Servidio ◽  
Pasquale Musso ◽  
Angela Costabile
Keyword(s):  
School Climate ◽  
Parental Monitoring ◽  
Structural Equation ◽  
Moral Disengagement ◽  
Ecological Factors ◽  
Equation Modeling ◽  
Environmental Predictors ◽  
Collaborative Strategies ◽  
Mediating Mechanisms

In recent years, studies have extensively explored both personal and environmental predictors of cyberbullying. Among these predictors, parental monitoring and school climate were often expected to be associated with cyberbullying behaviors. However, little is known about the mediating mechanisms through which these relations may develop. The present study aimed to expand the current research by testing a theoretical model including the mediating role of moral disengagement in the relations between parental monitoring (including less collaborative vs. more collaborative strategies), school climate, and cyberbullying behaviors. Five hundred and seventy-one Italian adolescents (54.5% male) aged 14 to 20 years were recruited from high schools. Measures included demographics and parental monitoring, school climate, moral disengagement and cyberbullying scales. To test the hypothesized model, we estimated full and partial mediation models by structural equation modeling. Results showed negative indirect links of parental monitoring (but only the more collaborative strategies) and school climate with cyberbullying via moral disengagement. Less collaborative strategies of parental monitoring were neither directly nor indirectly related to cyberbullying. The findings revealed moral disengagement as an important process in explaining how ecological factors, such as parenting behaviors and school environments, are associate with cyberbullying. Limitations, strengths, and implications for practice are presented.

scholarly journals Examining Individual and Ecological Predictors of the Self-Determination of Students with Disabilities

2007 ◽  
Vol 73 (4) ◽  
pp. 488-510 ◽  
Author(s):  
Karrie A. Shogren ◽  
Michael L. Wehmeyer ◽  
Susan B. Palmer ◽  
Jane Helen Soukup ◽  
Todd D. Little ◽  
...  
Keyword(s):  
General Education ◽  
Students With Disabilities ◽  
Structural Equation ◽  
Longitudinal Research ◽  
Ecological Factors ◽  
The Self ◽  
Self Determination ◽  
Equation Modeling ◽  
The Impact

This article examines the impact of multiple individual and ecological factors on the self-determination of students with learning disabilities, mild and moderate mental retardation, and other health impairments. Baseline data from a multistate, longitudinal research project evaluating interventions to promote self-determination were examined using structural equation modeling. The findings suggest that teachers viewed students' capacity for self-determination differently based on level of cognitive impairment, but not students' opportunities for self-determination. Capacity, opportunity, and transition empowerment predicted students' self-reported level of self-determination, but the degree to which students were included in general education did not. Significant differences emerged in the pattern of predictive relationships, however, depending on the measure of self-determination utilized. Also discussed are implications for research and practice.

scholarly journals Structural and Inter-individual Differentiation in Personality across the Adult Lifespan

2021 ◽  
Author(s):  
Gabriel Olaru ◽  
Kristin Jankowsky ◽  
Mathias Allemand
Keyword(s):  
Individual Differences ◽  
Big Five ◽  
Structural Equation ◽  
High Stability ◽  
Equation Modeling ◽  
Model Parameters ◽  
Cross Sectional ◽  
Psychological Constructs ◽  
Adult Lifespan ◽  
Individual Differentiation

The concept of differentiation describes increasing or decreasing similarities between inter-individual differences on psychological constructs, reflecting processes of specialization or adaptation. In this study, we studied age-differentiation in personality traits in 1) the association between trait domains, facets and nuances, 2) the correlations between trait domains, and 3) inter-individual differences at all trait levels. We used three large cross-sectional samples (Ns > 3,000) covering 16 to 90 years of age, and broad measures of the Big Five, Five-Factor and HEXACO models. We examined age effects on the model parameters using local structural equation modeling. We found a high stability of facet rank-ordering within trait domains, suggesting relatively stable trait domain compositions across age. Age-associated differences in the facet loadings were unsystematic and differed in direction across the three measures used. Extraversion-Openness correlations increased across age for all three measures, whereas an increase in Extraversion-Agreeableness and decrease in absolute Neuroticism-Extraversion correlations only replicated across the five-dimensional models. Inter-individual differences in personality varied most at the item or nuance level. In summary, personality differentiation is particularly evident at the lowest level and some trait domain correlations, but studies into this topic need to account for the heterogeneity of personality taxonomies and measures.

A Psychometric Study of the Quality Perception Questionnaire

2012 ◽  
Vol 71 (2) ◽  
pp. 101-106 ◽  
Author(s):  
Raffaele Cioffi† ◽  
Anna Coluccia ◽  
Fabio Ferretti ◽  
Francesca Lorini ◽  
Aristide Saggino ◽  
...  
Keyword(s):  
Structural Equation ◽  
Factor Model ◽  
Equation Modeling ◽  
Fit Indices ◽  
Quality Perception ◽  
Italian Survey ◽  
Confirmatory Factor ◽  
Instrument Measuring ◽  
Hospital Structures

The present paper reexamines the psychometric properties of the Quality Perception Questionnaire (QPQ), an Italian survey instrument measuring patients’ perceptions of the quality of a recent hospital admission experience, in a sample of 4400 patients (Mage = 56.42 years; SD = 19.71 years, 48.8% females). The 14-item survey measures four factors: satisfaction with medical doctors, nursing staff, auxiliary staff, and hospital structures. First, we tested two models using a confirmatory factor analysis (structural equation modeling): a four orthogonal factor and a four oblique factor model. The SEM fit indices and the χ² difference suggested the acceptance of the second model. We then did a simulation using a bootstrap with 1000 replications. Results confirmed the four oblique factor solution. Third, we tested whether there were significant differences with respect to age or sex. The multivariate general linear model showed no significant differences in the factors with respect to sex or age.

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