Publications by authors named "Bradley Olson"

Volvox carteri is an excellent system for investigating the origins of cell differentiation because it possesses just two cell types, reproductive gonidia and motile somatic cells, which evolved relatively recently. The somatic phenotype depends on the regA gene, which represses cell growth and reproduction, preventing cells expressing it from growing large enough to become gonidia. regA encodes a putative transcription factor and was generated in an undifferentiated ancestor of V.

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A new study uses Chlamydomonas reinhardtii to understand how cell size homeostasis emerges from stochastic individual cell behaviors within a population. The authors find that a simple power law model was a poor predictor of cell size regulation; rather, it is better explained by a modified threshold model.

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Background: Collective cell migration underlies many essential processes, including sculpting organs during embryogenesis, wound healing in the adult, and metastasis of cancer cells. At mid-oogenesis, Drosophila border cells undergo collective migration. Border cells round up into a small group at the pre-migration stage, detach from the epithelium and undergo a dynamic and highly regulated migration at the mid-migration stage, and stop at the oocyte, their final destination, at the post-migration stage.

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This article explores the magnifying lenses of the COVID-19 syndemic to highlight how people racialized as migrants and refugees have been-and continue to be-disproportionally harmed. We use empirical evidence collected in our scholarly/activist work in Europe, Africa, South Asia, and the United States to examine migrant injustice as being produced by a combination of power structures and relations working to maintain colonial global orders and inequalities. This is what has been defined as "border imperialism.

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Article Synopsis
  • - Multicellular evolution has led to diversification and increased complexity among species, with volvocine algae being an ideal model for studying this process due to their range of forms from unicellular to multicellular.
  • - Research on six volvocine genomes revealed a pattern of gradual gene loss alongside the utilization of specific key genes, indicating that significant evolutionary changes can occur with minimal genetic alterations.
  • - The study suggests that gene loss, rather than just the addition or rearrangement of genes, plays a crucial role in developing new and complex developmental traits through novel protein interactions and gene network dynamics.
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Article Synopsis
  • The research aimed to evaluate a short form of the Involvement in Alcoholics Anonymous scale (IAA-SF), focusing on its factor structure, internal consistency, and predictive validity.
  • The study involved two diverse samples—one from post-treatment adults in northern Illinois and another from recovery home residents across the U.S.—utilizing various analytical methods to assess the scale's effectiveness.
  • Results indicated that the IAA-SF measures three key involvement dimensions (Principles, Social, and Spiritual) with strong reliability, and highlighted that social and global involvement could predict better chances of maintaining abstinence after two years, showcasing its usefulness in understanding 12-step program participation.
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Introduction: The human papillomavirus (HPV) causes largely preventable cancers by completing a vaccination series. However, pediatric HPV vaccination rates remain low. Current evidence indicates that integrating five factors creates a high-quality recommendation associated with higher HPV vaccination rates.

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The evolution of multicellularity is a major evolutionary transition that underlies the radiation of many species in all domains of life, especially in eukaryotes. The volvocine green algae are an unconventional model system that holds great promise in the field given its genetic tractability, late transition to multicellularity, and phenotypic diversity. Multiple efforts at linking multicellularity-related developmental landmarks to key molecular changes, especially at the genome level, have provided key insights into the molecular innovations or lack thereof that underlie multicellularity.

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The evolution of germ-soma cellular differentiation represents a key step in the evolution of multicellular individuality. Volvox carteri and its relatives, the volvocine green algae, provide a model system for studying the evolution of cellular differentiation. In V.

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Efficient, more accurate reporting of maize (Zea mays L.) phenology, crop condition, and progress is crucial for agronomists and policy makers. Integration of satellite imagery with machine learning models has shown great potential to improve crop classification and facilitate in-season phenological reports.

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In 2018, in response to increasingly oppressive and widespread federal immigration enforcement actions in the United States (U.S.) and around the globe - including family separation, immigration raids, detention, deportation of people who have lived in the country for much of their lives - the Society for Community Research & Action produced a statement on the effects of deportation and forced separation on immigrants, their families, and communities (SCRA, 2018).

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Malaria continues to be a major global health problem, where disease transmission is deeply linked to the repeated blood feeding nature of the anautogenous mosquito. Given the tight link between blood feeding and disease transmission, understanding basic biology behind mosquito physiology is a requirement for developing effective vector-borne disease control strategies. In the mosquito, numerous loss of function studies with notable phenotypes demonstrate microRNAs (miRNAs) play significant roles in mosquito physiology.

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Multicellularity is the premier example of a major evolutionary transition in individuality and was a foundational event in the evolution of macroscopic biodiversity. The volvocine chlorophyte lineage is well suited for studying this process. Extant members span unicellular, simple colonial, and obligate multicellular taxa with germ-soma differentiation.

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Losses of floral pigmentation represent one of the most common evolutionary transitions in flower color, yet the genetic basis for these changes has been elucidated in only a handful of cases. Here we used crossing studies, bulk-segregant RNA sequencing, phylogenetic analyses and functional tests to identify the gene(s) responsible for the transition to white flowers in Iochroma loxense. Crosses between I.

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(laver) belongs to an ancient group of red algae (Bangiophyceae), is harvested for human food, and thrives in the harsh conditions of the upper intertidal zone. Here we present the 87.7-Mbp haploid genome (65.

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Despite its major impact on the evolution of Life on Earth, the transition to multicellularity remains poorly understood, especially in terms of its genetic basis. The volvocine algae are a group of closely related species that range in morphology from unicellular individuals (Chlamydomonas) to undifferentiated multicellular forms (Gonium) and complex organisms with distinct developmental programs and one (Pleodorina) or two (Volvox) specialized cell types. Modern genetic approaches, complemented by the recent sequencing of genomes from several key species, revealed that co-option of existing genes and pathways is the primary driving force for the evolution of multicellularity in this lineage.

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MYB transcription factors play an important role in regulating key plant developmental processes involving defense, cell shape, pigmentation, and root formation. Within this gene family, sequences containing an R2R3 MYB domain are the most abundant type and exhibit a wide diversity of functions. In this study, we identify 559 R2R3 MYB genes using whole genome data from four species of Solanaceae and reconstruct their evolutionary relationships.

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Biochemical analysis of proteins relies on accurate quantification of protein concentration. Detailed in this appendix are some commonly used methods for protein analysis, e.g.

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The transition to multicellularity has occurred numerous times in all domains of life, yet its initial steps are poorly understood. The volvocine green algae are a tractable system for understanding the genetic basis of multicellularity including the initial formation of cooperative cell groups. Here we report the genome sequence of the undifferentiated colonial alga, Gonium pectorale, where group formation evolved by co-option of the retinoblastoma cell cycle regulatory pathway.

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Proliferating cells actively control their size by mechanisms that are poorly understood. The unicellular green alga Chlamydomonas reinhardtii divides by multiple fission, wherein a 'counting' mechanism couples mother cell-size to cell division number allowing production of uniform-sized daughters. We identified a sizer protein, CDKG1, that acts through the retinoblastoma (RB) tumor suppressor pathway as a D-cyclin-dependent RB kinase to regulate mitotic counting.

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Sex-determining regions (SDRs) or mating-type (MT) loci in two sequenced volvocine algal species, Chlamydomonas reinhardtii and Volvox carteri, exhibit major differences in size, structure, gene content, and gametolog differentiation. Understanding the origin of these differences requires investigation of MT loci from related species. Here, we determined the sequences of the minus and plus MT haplotypes of the isogamous 16-celled volvocine alga, Gonium pectorale, which is more closely related to the multicellular V.

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Research has shown employment to be a central mediator to sustained recovery and community reentry for substance abusers; however, heroin users have lower employment rates and report lower mean incomes than other drug users. The authors of the present study assessed income generating behaviors of substance users recruited from substance abuse treatment facilities (N=247). Heroin users had higher mean incomes from illegal sources.

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The relationships between motivation, treatment readiness, and abstinence self-efficacy were examined among a sample of ex-offenders exiting inpatient treatment for substance use disorders. Hierarchical linear regression was conducted to examine changes in participants' motivation levels in relation to abstinence self-efficacy beyond what would be expected from treatment readiness and substance use. Abstinence self-efficacy predicted significant decreases in motivation whereas treatment readiness and substance use predicted significant increases.

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Millions of people are infected each year by arboviruses (arthropod-borne viruses) such as chikungunya, dengue, and West Nile viruses, yet for reasons that are largely unknown, only a relatively small number of mosquito species are able to transmit arboviruses. Understanding the complex factors that determine vector competence could facilitate strategies for controlling arbovirus infections. Apoptosis is a potential antiviral defense response that has been shown to be important in other virus-host systems.

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