A Historiometric Examination of Machiavellianism and a New Taxonomy of Leadership

Although researchers have extensively examined the relationship between charismatic leadership and Machiavellianism (Deluga, 2001; Gardner & Avolio, 1995; House & Howell, 1992), there has been a lack of investigation of Machiavellianism in relation to alternative forms of outstanding leadership. Thus, the purpose of this investigation was to examine the relationship between Machiavellianism and a new taxonomy of outstanding leadership comprised of charismatic, ideological, and pragmatic leaders. Using an historiometric approach, raters assessed Machiavellianism via the communications of 120 outstanding leaders in organizations across the domains of business, political, military, and religious institutions. Academic biographies were used to assess twelve general performance measures as well as twelve general controls and five communication specific controls. The results indicated that differing levels of Machiavellianism is evidenced across the differing leader types as well as differing leader orientation. Additionally, Machiavellianism appears negatively related to performance, though less so when type and orientation are taken into account.Yeshttps://us.sagepub.com/en-us/nam/manuscript-submission-guideline

Comprehensive analysis of epigenetic clocks reveals associations between disproportionate biological ageing and hippocampal volume

The concept of age acceleration, the difference between biological age and chronological age, is of growing interest, particularly with respect to age-related disorders, such as Alzheimer’s Disease (AD). Whilst studies have reported associations with AD risk and related phenotypes, there remains a lack of consensus on these associations. Here we aimed to comprehensively investigate the relationship between five recognised measures of age acceleration, based on DNA methylation patterns (DNAm age), and cross-sectional and longitudinal cognition and AD-related neuroimaging phenotypes (volumetric MRI and Amyloid-β PET) in the Australian Imaging, Biomarkers and Lifestyle (AIBL) and the Alzheimer’s Disease Neuroimaging Initiative (ADNI). Significant associations were observed between age acceleration using the Hannum epigenetic clock and cross-sectional hippocampal volume in AIBL and replicated in ADNI. In AIBL, several other findings were observed cross-sectionally, including a significant association between hippocampal volume and the Hannum and Phenoage epigenetic clocks. Further, significant associations were also observed between hippocampal volume and the Zhang and Phenoage epigenetic clocks within Amyloid-β positive individuals. However, these were not validated within the ADNI cohort. No associations between age acceleration and other Alzheimer’s disease-related phenotypes, including measures of cognition or brain Amyloid-β burden, were observed, and there was no association with longitudinal change in any phenotype. This study presents a link between age acceleration, as determined using DNA methylation, and hippocampal volume that was statistically significant across two highly characterised cohorts. The results presented in this study contribute to a growing literature that supports the role of epigenetic modifications in ageing and AD-related phenotypes

Uncovering the heterogeneity and temporal complexity of neurodegenerative diseases with Subtype and Stage Inference

The heterogeneity of neurodegenerative diseases is a key confound to disease understanding and treatment development, as study cohorts typically include multiple phenotypes on distinct disease trajectories. Here we introduce a machine-learning technique\u2014Subtype and Stage Inference (SuStaIn)\u2014able to uncover data-driven disease phenotypes with distinct temporal progression patterns, from widely available cross-sectional patient studies. Results from imaging studies in two neurodegenerative diseases reveal subgroups and their distinct trajectories of regional neurodegeneration. In genetic frontotemporal dementia, SuStaIn identifies genotypes from imaging alone, validating its ability to identify subtypes; further the technique reveals within-genotype heterogeneity. In Alzheimer\u2019s disease, SuStaIn uncovers three subtypes, uniquely characterising their temporal complexity. SuStaIn provides fine-grained patient stratification, which substantially enhances the ability to predict conversion between diagnostic categories over standard models that ignore subtype (p = 7.18 7 10 124 ) or temporal stage (p = 3.96 7 10 125 ). SuStaIn offers new promise for enabling disease subtype discovery and precision medicine

Text as Data in Interest Group Research

Text analysis is highly useful for scholars working on lobbying and interest groups. It is a method through which organized interests, their positions on issues, and the frames that they employ can be identified within bodies of text. This technique allows scholars to measure access to different types of venues and the policy positions that groups express. It can reveal patterns of populations and communities that can be used as (in)dependent variables. In turn, these can be linked to characteristics of organized interests, the context in which they operate and policy outcomes

Comparative Interest Group Research

There are challenges to the development of explanatory models of interest group behavior that are valid across a wide range of countries. The position of interest groups in between the policy process and the society and the economy means that a lot of potentially important explanatory factors cannot be theoretically isolated. This creates a fundamental tension between the aspiration to maximize the external, cross-system validity of research findings and the meaningful embedding in country-specific histories, economic structures and societies. This theoretical challenge is conceptually acknowledged in many contemporary studies but still limits the theoretical progress in the field. This contribution discusses the distinct ways in which interest group research has historically dealt with inherent challenges of comparative research designs

Comparative Interest Group Research

There are challenges to the development of explanatory models of interest group behavior that are valid across a wide range of countries. The position of interest groups in between the policy process and the society and the economy means that a lot of potentially important explanatory factors cannot be theoretically isolated. This creates a fundamental tension between the aspiration to maximize the external, cross-system validity of research findings and the meaningful embedding in country-specific histories, economic structures and societies. This theoretical challenge is conceptually acknowledged in many contemporary studies but still limits the theoretical progress in the field. This contribution discusses the distinct ways in which interest group research has historically dealt with inherent challenges of comparative research designs

Group Populations

Scholars from a number of disciplines have shown interest in the enumeration of the interest groups active in particular political systems or the numbers of associations present in a given civil society (e.g., Halpin & Jordan, 2012). Descriptive “maps” of the group population are of critical importance for a range of substantive scholarly interests and is a commodity for several adjacent research methods such as surveys, elite interviewing, and issue sampling. This map will look somewhat different depending on the research interest at stake, and researchers will have to define the limits of their population, critically assess the adequacy of data sources available, and decide upon characteristics and categories of classification