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Drosophila suzukii, or spotted-wing drosophila, is now an established pest in many parts of the world, causing significant damage to numerous fruit crop industries. Native to East Asia, D. suzukii infestations started in the United States a decade ago, occupying a wide range of climates. To better understand invasion ecology of this pest, knowledge of past migration events, population structure, and genetic diversity is needed. In this study, we sequenced whole genomes of 237 individual flies collected across the continental United States, as well as several sites in Europe, Brazil, and Asia, to identify and analyze hundreds of thousands of genetic markers. We observed strong population structure between Western and Eastern US populations, but no evidence of any population structure between different latitudes within the continental United States, suggesting that there are no broad-scale adaptations occurring in response to differences in winter climates. We detect admixture from Hawaii to the Western United States and from the Eastern United States to Europe, in agreement with previously identified introduction routes inferred from microsatellite analysis. We also detect potential signals of admixture from the Western United States back to Asia, which could have important implications for shipping and quarantine policies for exported agriculture. We anticipate this large genomic dataset will spur future research into the genomic adaptations underlying D. suzukii pest activity and development of novel control methods for this agricultural pest.

The desire to support student learning and professional development, in combination with accreditation requirements, necessitates the need to evaluate the learning environment of educational programs. The Health Education Learning Environment Survey (HELES) is a recently-developed global measure of the learning environment for health professions programs. This paper provides evidence of the applicability of the HELES for evaluating the learning environment across four health professions programs: medicine, nursing, occupational therapy and pharmaceutical sciences. Two consecutive years of HELES data were collected from each program at a single university (year 1 = 552 students; year 2 = 745 students) using an anonymous online survey. Reliability analyses across programs and administration years supported the reliability of the tool. Two-way factorial ANOVAs with program and administration year as the independent variables indicated statistically- and practically-significant differences across programs for four of the seven scales. Overall, these results support the use of the HELES to evaluate student perceptions of the learning environment multiple of health professions programs.

Maternally transmitted Wolbachia, Spiroplasma, and Cardinium bacteria are common in insects [1], but their interspecific spread is poorly understood. Endosymbionts can spread rapidly within host species by manipulating host reproduction, as typified by the global spread of wRi Wolbachia observed in Drosophila simulans [2, 3]. However, because Wolbachia cannot survive outside host cells, spread between distantly related host species requires horizontal transfers that are presumably rare [4-7]. Here, we document spread of wRi-like Wolbachia among eight highly diverged Drosophila hosts (10-50 million years) over only about 14,000 years (5,000-27,000). Comparing 110 wRi-like genomes, we find ≤0.02% divergence from the wRi variant that spread rapidly through California populations of D. simulans. The hosts include both globally invasive species (D. simulans, D. suzukii, and D. ananassae) and narrowly distributed Australian endemics (D. anomalata and D. pandora) [8]. Phylogenetic analyses that include mtDNA genomes indicate introgressive transfer of wRi-like Wolbachia between closely related species D. ananassae, D. anomalata, and D. pandora but no horizontal transmission within species. Our analyses suggest D. ananassae as the Wolbachia source for the recent wRi invasion of D. simulans and D. suzukii as the source of Wolbachia in its sister species D. subpulchrella. Although six of these wRi-like variants cause strong cytoplasmic incompatibility, two cause no detectable reproductive effects, indicating that pervasive mutualistic effects [9, 10] complement the reproductive manipulations for which Wolbachia are best known. "Super spreader" variants like wRi may be particularly useful for controlling insect pests and vector-borne diseases with Wolbachia transinfections [11].

The evolutionary importance of hybridization and introgression has long been debated. Hybrids are usually rare and unfit, but even infrequent hybridization can aid adaptation by transferring beneficial traits between species. Here we use genomic tools to investigate introgression in Heliconius, a rapidly radiating genus of neotropical butterflies widely used in studies of ecology, behaviour, mimicry and speciation. We sequenced the genome of Heliconius melpomene and compared it with other taxa to investigate chromosomal evolution in Lepidoptera and gene flow among multiple Heliconius species and races. Among 12,669 predicted genes, biologically important expansions of families of chemosensory and Hox genes are particularly noteworthy. Chromosomal organization has remained broadly conserved since the Cretaceous period, when butterflies split from the Bombyx (silkmoth) lineage. Using genomic resequencing, we show hybrid exchange of genes between three co-mimics, Heliconius melpomene, Heliconius timareta and Heliconius elevatus, especially at two genomic regions that control mimicry pattern. We infer that closely related Heliconius species exchange protective colour-pattern genes promiscuously, implying that hybridization has an important role in adaptive radiation.

VectorBase (http://www.vectorbase.org) is a NIAID-supported bioinformatics resource for invertebrate vectors of human pathogens. It hosts data for nine genomes: mosquitoes (three Anopheles gambiae genomes, Aedes aegypti and Culex quinquefasciatus), tick (Ixodes scapularis), body louse (Pediculus humanus), kissing bug (Rhodnius prolixus) and tsetse fly (Glossina morsitans). Hosted data range from genomic features and expression data to population genetics and ontologies. We describe improvements and integration of new data that expand our taxonomic coverage. Releases are bi-monthly and include the delivery of preliminary data for emerging genomes. Frequent updates of the genome browser provide VectorBase users with increasing options for visualizing their own high-throughput data. One major development is a new population biology resource for storing genomic variations, insecticide resistance data and their associated metadata. It takes advantage of improved ontologies and controlled vocabularies. Combined, these new features ensure timely release of multiple types of data in the public domain while helping overcome the bottlenecks of bioinformatics and annotation by engaging with our user community.

The Medical School Learning Environment Survey (MSLES) was used with a sample of 311 undergraduate medical students in British Columbia, Canada, to assess the seven scales of Medical Breadth of Interest, Personal Breadth of Interest, Emotional Climate, Flexibility, Meaningful Learning Experience, Organization, Nurturance and Student-Student Interaction. Confirmatory factor analysis was used to support the validity of the MSLES when used with this sample.

Research indicates that African Americans living in an oppressive society may be at an increased risk of experiencing psychological symptoms. Oppressive society has been defined as the continual denial of resources to marginalized groups. This study examined the possible moderating effects of racial socialization (using Scale of Racial Socialization-Adolescent) in the relationship between poverty and psychological symptoms (externalizing and internalizing symptoms). The sample consisted of 105 African American adolescents, aged 11 to 15, from a large midwestern city. Racial socialization was expected to reduce psychological symptomatology. There was an unexpected finding of a positive relationship between racial socialization and externalizing symptoms. Although significant moderating effects were found for racial socialization, no protective effect was demonstrated in this study. Future research directions are discussed. (Contains 4 tables, 2 figures and 2 notes.)

This review describes the evolution of time-resolved electrospray ionization mass spectrometry (TRESI-MS), a technology that was developed in large part at Western University. TRESI-MS was initially designed to characterize rapid chemical and biochemical reactions occurring on the millisecond time scale without need for a chromophore. Early TRESI-MS setups usually consisted of continuous-flow rapid mixers with a fixed tee for analysis of a single time point, and later adjustable reaction chamber devices allowing for automatic tracking of the reaction over time. Advances in instrumentation design over the years have resulted in improved time resolution, with microfluidic device implementation allowing for coupling to hydrogen-deuterium exchange (HDX) experiments. Areas of application that will be discussed include the investigation of protein folding intermediates, identification of enzyme-substrate intermediates in the pre-steady state, and the use of time- resolved HDX to study the dynamics of weakly structured protein regions. While some limitations still persist with the method, the continued development of TRESI-MS and related approaches paves the way to a promising future and the study of unexplored application areas. Key words: mass spectrometry, electrospray ionization mass spectrometry, time-resolved, kinetics, protein folding, enzyme catalysis, hydrogen-deuterium exchange. La presente etude decrit l'evolution de la spectrometrie de masse a ionisation par electronebulisation resolue en temps (TRESI-MS), une technologie qui fut elaboree en grande partie a la Western University. A l'origine, la TRESI-MS fut concue pour caracteriser les reactions chimiques et biochimiques rapides qui se produisaient a l'echelle de la milliseconde sans presence necessaire d'un chromophore. Les premiers appareils de TRESI-MS consistaient generalement en des melangeurs rapides a flux continu equipes d'un << tee >> fixe permettant d'effectuer des analyses ponctuelles, puis, plus tard, en des dispositifs a chambres de reaction ajustables offrant la possibilite de realiser le suivi automatique des reactions au cours du temps. Des progres realises dans la conception de l'instrumentation au fil des ans ont permis d'ameliorer la resolution temporelle, notamment la mise en place d'appareils de microfluidique qui permirent de realiser des experiences de couplage avec l'echange hydrogene- deuterium (HDX). Nous presenterons, entre autres champs d'application, l'etude des intermediaires du repliement proteique, l'identification des intermediaires du complexe enzyme-substrat dans l'etat de pre-equilibre et l'utilisation de HDX resolu en temps pour l'etude de la dynamique des regions proteiques faiblement structurees. Bien qu'elle montre encore quelques limites, l'amelioration continue de la TRESI-MS et des techniques auxquelles elle est associee ouvre la voie a un avenir prometteur et a l'etude de champs d'application inexplores. [Traduit par la Redaction] Mots-cles : spectrometrie de masse, spectrometrie de masse a ionisation par electronebulisation, resolution en temps, cinetique, repliement proteique, catalyse enzymatique, echange hydrogene-deuterium., Introduction Mass spectrometry (MS) has become one of the most sensitive bioanalytical tools for the structural characterization of (bio)molecules, driven by continual instrumental advancements since its origin stemming from the [...]