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In this chapter, we describe intervention efforts aimed at promoting maintenance behaviors in romantic relationships and the factors that influence these initiatives. We highlight current cultural forces surrounding clinical and educational practices, the definitions and theories that inform interventions to sustain and enhance partners’ maintenance behaviors, and important considerations for increasing the effectiveness of these interventions. The interventions featured in our review focus on enhancing positive aspects of relationships or mitigating threat to relationship maintenance processes within the cultural context of contemporary relationships. Suggestions for advancing the field include further research on the relevance of specific maintenance strategies and theories of change across the life course, the influence of cultural context and resilience on maintenance processes, unintended consequences of relationship maintenance interventions, and the evaluation process for interventions promoting maintenance behaviors.
The prevalence and impact of motor coordination difficulties in children with copy number variants associated with neurodevelopmental disorders (ND-CNVs) remains unknown. This study aims to advance understanding of motor coordination difficulties in children with ND-CNVs and establish relationships between intelligence quotient (IQ) and psychopathology.
169 children with an ND-CNV (67% male, median age = 8.88 years, range 6.02–14.81) and 72 closest-in-age unaffected siblings (controls; 55% male, median age = 10.41 years, s.d. = 3.04, range 5.89–14.75) were assessed with the Developmental Coordination Disorder Questionnaire, alongside psychiatric interviews and standardised assessments of IQ.
The children with ND-CNVs had poorer coordination ability (b = 28.98, p < 0.001) and 91% of children with an ND-CNV screened positive for suspected developmental coordination disorder, compared to 19% of controls (OR = 42.53, p < 0.001). There was no difference in coordination ability between ND-CNV genotypes (F = 1.47, p = 0.184). Poorer coordination in children with ND-CNV was associated with more attention deficit hyperactivity disorder (ADHD) (β = −0.18, p = 0.021) and autism spectrum disorder trait (β = −0.46, p < 0.001) symptoms, along with lower full-scale (ß = 0.21, p = 0.011), performance (β = −0.20, p = 0.015) and verbal IQ (β = 0.17, p = 0.036). Mediation analysis indicated that coordination ability was a full mediator of anxiety symptoms (69% mediated, p = 0.012), and a partial mediator of ADHD (51%, p = 0.001) and autism spectrum disorder trait symptoms (66%, p < 0.001) as well as full scale IQ (40%, p = 0.002), performance IQ (40%, p = 0.005) and verbal IQ (38%, p = 0.006) scores.
The findings indicate that poor motor coordination is highly prevalent and closely linked to risk of mental health disorder and lower intellectual function in children with ND-CNVs. Future research should explore whether early interventions for poor coordination ability could ameliorate neurodevelopmental risk.
The chromosome complement (karyotype) often differs between related mammalian species (including humans vs chimpanzees), such that evolutionary biologists muse whether chromosomal difference is a cause or a consequence of speciation. The common shrew is an excellent model to investigate this problem because of its many geographical races (potential species) differing chromosomally, and its several sibling species (recently speciated forms) that are also chromosomally different. This system is an exceptional opportunity to investigate the role of chromosomes in speciation and this volume reflects detailed research following these approaches. Highlights include the demonstration that chromosomal re-arrangements can be associated with complete loss of gene flow and thus speciation and that selection within species hybrid zones may lead to de-speciation rather than speciation. This book represents an extraordinarily detailed consideration of the role of chromosomes in speciation in one astonishing species, providing insights to those interested in mammalian diversity, chromosomal evolution and speciation.
The past decade has seen the development of services for adults presenting with symptoms of autism spectrum disorder (ASD) in the UK. Compared with children, little is known about the phenotypic and genetic characteristics of these patients.
This e-cohort study aimed to examine the phenotypic and genetic characteristics of a clinically presenting sample of adults diagnosed with ASD by specialist services.
Individuals diagnosed with ASD as adults were recruited by the National Centre for Mental Health and completed self-report questionnaires, interviews and provided DNA; 105 eligible individuals were matched to 76 healthy controls. We investigated demographics, social history and comorbid psychiatric and physical disorders. Samples were genotyped, copy number variants (CNVs) were called and polygenic risk scores were calculated.
Of individuals with ASD, 89.5% had at least one comorbid psychiatric diagnosis, with depression (62.9%) and anxiety (55.2%) being the most common. The ASD group experienced more neurological comorbidities than controls, particularly migraine headache. They were less likely to have married or be in work, and had more alcohol-related problems. There was a significantly higher load of autism common genetic variants in the adult ASD group compared with controls, but there was no difference in the rate of rare CNVs.
This study provides important information about psychiatric comorbidity in adult ASD, which may inform clinical practice and patient counselling. It also suggests that the polygenic load of common ASD-associated variants may be important in conferring risk within the non-intellectually disabled population of adults with ASD.
The excellent fossil record of the past few million years, combined with the overwhelming similarity of the biota to extant species, provides an outstanding opportunity for understanding paleoecological and macroevolutionary patterns and processes within a rigorous biological framework. Unfortunately, this potential has not been fully exploited because of lack of well-sampled time series and adequate statistical analysis. Nevertheless, four basic patterns appear to be of general significance. First, a major pulse of extinction occurred 1–2 m.y. ago in many ocean basins, more or less coincident with the intensification of glaciation in the Northern Hemisphere. Rates of origination also increased greatly but were more variable in magnitude and timing. The fine-scale correlation of these evolutionary events with changes in climate is poorly understood. Similar events probably occurred on land but have not been tested adequately. Second, rates of origination and extinction in the oceans waned after the pulse of extinction, especially during the past 1 m.y. Thus, most marine species originated long before the Pleistocene under very different environmental circumstances, suggesting that they are “exapted” rather than adapted to their present ecological circumstances. The same may be true for many terrestrial groups, but not for the mammals or fresh-water fishes that have continued to undergo speciation throughout the Pleistocene. Third, community membership of late Pleistocene coral reef communities was more stable than expected by chance. These are the only paleoecological data adequate to test hypotheses of community stability, so that we do not know whether community structure involving other taxa or environments typically reflects more than the collective behavior of individual species distributions. Regardless, the strong evidence for nearly universal exaptation of ecological characteristics argues strongly against ideas of coevolution of species in communities. Finally, ecological communities were profoundly altered by human activities long before modern ecological studies began. Holocene paleontological, archeological, and historical data constitute the only ecological baseline for “pristine” ecological communities before significant human disturbance. Holocene records should be much more extensively used as a baseline for Recent ecological studies and for conservation and management.
Objectives: Apathy is a debilitating symptom of Huntington’s disease (HD) and manifests before motor diagnosis, making it an excellent therapeutic target in the preclinical phase of Huntington’s disease (prHD). HD is a neurological genetic disorder characterized by cognitive and motor impairment, and psychiatric abnormalities. Apathy is not well characterized within the prHD. In previous literature, damage to the caudate and putamen has been correlated with increased apathy in other neurodegenerative and movement disorders. The objective of this study was to determine whether apathy severity in individuals with prHD is related to striatum volumes and cognitive control. We hypothesized that, within prHD individuals, striatum volumes and cognitive control scores would be related to apathy. Methods: We constructed linear mixed models to analyze striatum volumes and cognitive control, a composite measure that includes tasks assessing with apathy scores from 797 prHD participants. The outcome variable for each model was apathy, and the independent variables for the four separate models were caudate volume, putamen volume, cognitive control score, and motor symptom score. We also included depression as a covariate to ensure that our results were not solely related to mood. Results: Caudate and putamen volumes, as well as measures of cognitive control, were significantly related to apathy scores even after controlling for depression. Conclusions: The behavioral apathy expressed by these individuals was related to regions of the brain commonly associated with isolated apathy, and not a direct result of mood symptoms. (JINS, 2019, 25, 462–469)
While research on the role of employees’ characteristics as core to transformational leadership theory is burgeoning, limited research has focused on the differing aspects of employees’ self-determined motivation as mediating mechanism through which transformational leadership may impact outcomes. Drawing on the self-determined theory of motivation, we build and test a theoretical model linking employees’ perceptions of transformational leadership with engagement through an intervening variable of differing aspects of employees’ self-determined motivation. Data from a sample of 155 participants revealed that employees’ perceptions of transformational leadership were positively related to employees’ self-determined motivation (intrinsic, autonomous, and controlled) and work engagement. Specifically, self-determined motivation (intrinsic, autonomous) was positively linked with work engagement while intrinsic, autonomous and controlled dimensions of self-determined motivation mediated the relationship between transformational leadership and work engagement. We discuss the theoretical and practical implications of the results.
This chapter explores whether and how genomic resources can be protected by the communities from, or countries in which they are accessed. Specifically, it asks whether the Nagoya Protocol on Access and Benefit-Sharing can be an effective mechanism to reassure communities about the sharing of gene sequencing data. These questions are of particular importance to Indigenous peoples and local communities, as many have troubling historical experiences with colonization and associated natural resource exploitation. Many Indigenous and local communities (ILCs) live in developing countries, which are particularly sensitive to access and benefit-sharing (ABS) issues. Different but equally serious challenges exist for Indigenous peoples in developed countries like Canada, Australia, New Zealand and elsewhere. Until outcomes of implementation of the Nagoya Protocol are captured, Indigenous peoples and Local Communities (IPLCs) remain in a quandary as to how to protect digitized genetic resources within their territories or under their jurisdiction. To advance our understanding of legal and regulatory options, this chapter integrates normative and positive perspectives on the mechanisms for access and benefit-sharing in the age of digital biology.
Starbursts are finite periods of intense star formation (SF) that can dramatically impact the evolutionary state of a galaxy. Recent results suggest that starbursts in dwarf galaxies last longer and are distributed over more of the galaxy than previously thought, with star formation efficiencies (SFEs) comparable to spiral galaxies, much higher than those typical of non-bursting dwarfs. This difference might be explainable if the starburst mode is externally triggered by gravitational interactions with other nearby systems. We present new, sensitive neutral hydrogen observations of 18 starburst dwarf galaxies, which are part of the STARburst IRregular Dwarf Survey (STARBIRDS) and each were mapped with the Green Bank Telescope (GBT) and/or Parkes Telescope in order to study the low surface brightness gas distributions, a common tracer for tidal interactions.