Multinational evaluation of the measurement invariance of the level of personality functioning scale–brief form 2.0: comparison of student and community samples across seven countries

DSM-5’s Level of Personality Functioning Scale (LPFS) was introduced as a dimensional rating of impairments in self- and interpersonal functioning, and the LPFS – Brief Form (LPFS-BF) was the first published corresponding self-report. The updated LPFS-BF 2.0 has been translated into several languages and international research supports many of the instrument’s psychometric properties; however, its measurement invariance has only been evaluated across a few countries. This study expands previous studies as an introductory step in a global evaluation of the LPFS-BF 2.0’s measurement invariance. Archival data (N = 5,618, 57% female) from seven countries (Canada, Chile, Denmark, Germany, Italy, United Arab Emirates, United States of America) were used for this study. Participants were recruited from both community (n = 4,677) and student (n = 941) populations. After confirming adequate model fit separately in the community and student samples, we evaluated a series of increasingly stringent model comparisons to test three aspects of measurement invariance (configural, metric, scalar) and then examined latent mean differences across countries. Full scalar invariance was supported in the community sample and partial scalar invariance was supported in the student sample. Evaluation of latent mean differences revealed multiple significant differences. Overall, the LPFS-BF 2.0 appears to assess self- and interpersonal functioning impairment similarly across the included countries. Findings are discussed through the lenses of the cultures from which participants were recruited, as well as in the context of alternative explanations. Limitations, plans for future research, and implications for both research and clinical practice are offered

Plant-mediated effects on a toxin-sequestering aphid and its endoparasitoid

Variation in plant morphology and chemistry can directly influence the performance of insect herbivores. A growing number of studies indicate that plants can also influence the performance of the natural enemies of the herbivores. Plant species in the Brassicaceae produce secondary compounds known as glucosinolates (GLS) whose hydrolysis products are potentially toxic to many herbivores. Some specialist insects are known to sequester the GLS, but up to date, there is no data on impact of GLS sequestration by insect herbivores on the performance of their parasitoids. We asked whether the performance of the GLS-sequestering aphid Brevicoryne brassicae and its parasitoid Diaeretiella rapae were affected by the host plants on which they feed. We selected four host plant species, one cultivar of Brassica oleracea and B. napus, and two wild species, B. nigra and Sinapis arvensis. Among other traits, these species differ in GLS content and composition as well as in some morphological characteristics. Population growth rate of Br brassicae was not affected by host plant species. However, adult aphids were the smallest, but also lived the longest when they had developed on the B. oleracea cultivar. Parasitoids were larger when their aphid hosts fed on the wild species. Unexpectedly, parasitism rate was lower on B. oleracea. Thus, variation in host plant characteristics had an impact on the fitness of the parasitoid through its aphid host. In contrast to previous studies, which have shown that sequestration is a good defence mechanism against predators, we did not observe that Br brassicae benefits from the sequestration of GLS to limit attacks by its main parasitoid

NEO: non equilibrium sampling on the orbits of a deterministic transform

Sampling from a complex distribution π and approximating its intractable normalizing constant Z are challenging problems. In this paper, a novel family of importance samplers (IS) and Markov chain Monte Carlo (MCMC) samplers is derived. Given an invertible map T, these schemes combine (with weights) elements from the forward and backward Orbits through points sampled from a proposal distribution ρ. The map T does not leave the target π invariant, hence the name NEO, standing for Non-Equilibrium Orbits. NEO-IS provides unbiased estimators of the normalizing constant and self-normalized IS estimators of expectations under π while NEO-MCMC combines multiple NEO-IS estimates of the normalizing constant and an iterated sampling-importance resampling mechanism to sample from π. For T chosen as a discrete-time integrator of a conformal Hamiltonian system, NEO-IS achieves state-of-the art performance on difficult benchmarks and NEO-MCMC is able to explore highly multimodal targets. Additionally, we provide detailed theoretical results for both methods. In particular, we show that NEO-MCMC is uniformly geometrically ergodic and establish explicit mixing time estimates under mild conditions

The Tri-trophic Niche Concept and Adaptive Radiation of Phytophagous Insects

A conceptual divide exists between ecological and evolutionary approaches to understanding adaptive radiation, although the phenomenon is inherently both ecological and evolutionary. This divide is evident in studies of phytophagous insects, a highly diverse group that has been frequently investigated with the implicit or explicit goal of understanding its diversity. Whereas ecological studies of phytophagous insects increasingly recognize the importance of tri-trophic interactions as determinants of niche dimensions such as host-plant associations, evolutionary studies typically neglect the third trophic level. Here we attempt to reconcile ecological and evolutionary approaches through the concept of the ecological niche. We specifically present a tri-trophic niche concept as a foil to the traditional bi-trophic niche concept for phytophagous insects. We argue that these niche concepts have different implications for understanding herbivore community structure, population divergence, and evolutionary diversification. To this end, we offer contrasting empirical predictions of bi- and tri-trophic niche concepts for patterns of community structure, the process of population divergence, and patterns of evolutionary diversification of phytophagous insects