Walrus ivory was a prized commodity in medieval Europe and was supplied by Norse intermediaries who expanded across the North Atlantic, establishing settlements in Iceland and Greenland. However, the precise sources of the traded ivory have long remained unclear, raising important questions about the sustainability of commercial walrus harvesting, the extent to which Greenland Norse were able to continue mounting their own long-range hunting expeditions, and the degree to which they relied on trading ivory with the various Arctic Indigenous peoples that they were starting to encounter. We use high-resolution genomic sourcing methods to track walrus artifacts back to specific hunting grounds, demonstrating that Greenland Norse obtained ivory from High Arctic waters, especially the North Water Polynya, and possibly from the interior Canadian Arctic.
View Article and Find Full Text PDFWhole-genome duplication (WGD) occurs in all kingdoms and impacts speciation, domestication, and cancer outcome. However, doubled DNA management can be challenging for nascent polyploids. The study of within-species polyploidy (autopolyploidy) permits focus on this DNA management aspect, decoupling it from the confounding effects of hybridization (in allopolyploid hybrids).
View Article and Find Full Text PDFWhen given a choice, people will avoid cognitively effortful courses of action because the experience of effort is evaluated as aversive and costly. At the same time, a body of work spanning psychology, economics, and neuroscience suggests that goods, actions, and experiences are often evaluated in the context in which they are encountered, rather in absolute terms. To probe the extent to which the evaluation of cognitive effort is also context-dependent, we had participants learn associations between unique stimuli and subjective demand levels across low-demand and high-demand contexts.
View Article and Find Full Text PDFMeiotic crossovers (COs) generate genetic diversity and are crucial for viable gamete production. Plant COs are typically limited to 1-3 per chromosome pair, constraining the development of improved varieties, which in wheat is exacerbated by an extreme distal localisation bias. Advances in wheat genomics and related technologies provide new opportunities to investigate, and possibly modify, recombination in this important crop species.
View Article and Find Full Text PDFRapid global warming is severely impacting Arctic ecosystems and is predicted to transform the abundance, distribution and genetic diversity of Arctic species, though these linkages are poorly understood. We address this gap in knowledge using palaeogenomics to examine how earlier periods of global warming influenced the genetic diversity of Atlantic walrus (), a species closely associated with sea ice and shallow-water habitats. We analysed 82 ancient and historical Atlantic walrus mitochondrial genomes (mitogenomes), including now-extinct populations in Iceland and the Canadian Maritimes, to reconstruct the Atlantic walrus' response to Arctic deglaciation.
View Article and Find Full Text PDFLinkage and candidate gene studies have identified several breast cancer susceptibility genes, but the overall contribution of coding variation to breast cancer is unclear. To evaluate the role of rare coding variants more comprehensively, we performed a meta-analysis across three large whole-exome sequencing datasets, containing 26,368 female cases and 217,673 female controls. Burden tests were performed for protein-truncating and rare missense variants in 15,616 and 18,601 genes, respectively.
View Article and Find Full Text PDFNonunion and segmental bone defects are complex issues in orthopedic trauma. The use of endothelial progenitor cells (EPCs), as part of a cell-based therapy for bone healing is a promising approach. In preclinical studies, culture medium (CM) is commonly used to deliver EPCs to the defect site, which has the potential for immunogenicity in humans.
View Article and Find Full Text PDFPerceived pain can be viewed because of a competition between nociceptive inputs and other competing goals, such as performing a demanding cognitive task. Task performance, however, suffers when cognitively fatigued. We therefore predicted that cognitive fatigue would weaken the pain-reducing effects of performing a concurrent cognitive task, which would indicate a causal link between fatigue and heightened pain sensitivity.
View Article and Find Full Text PDFJapanese knotweed () is native to East Asia, but has been introduced to the West where it is a noxious invasive weed. Taxonomically, Japanese knotweed is placed within subtribe Reynoutriinae (Polygonaceae), which also contains the austral genus (incl. ) and north temperate .
View Article and Find Full Text PDFDuring the pandemic, older adults were perceived as a vulnerable group without considering their various strengths. This study explored the associations between character strengths and resilience, and verified if some of these could predict resilience during the COVID-19 pandemic. A sample of 92 participants (women = 79.
View Article and Find Full Text PDFBackground: Given the rapidly evolving pandemic of COVID-19 in 2020, authorities focused on the repurposing of available drugs to develop timely and cost-effective therapeutic strategies. Evidence suggested the potential utility of remdesivir in the framework of an early access program. REMDECO-19 is a multicenter national cohort study assessing the ability of remdesivir to improve the outcome of patients hospitalized with COVID-19.
View Article and Find Full Text PDFWheat is a major cereal crop that possesses a large allopolyploid genome formed through hybridisation of tetraploid and diploid progenitors. During meiosis, crossovers (COs) are constrained in number to 1-3 per chromosome pair that are predominantly located towards the chromosome ends. This reduces the probability of advantageous traits recombining onto the same chromosome, thus limiting breeding.
View Article and Find Full Text PDFFANCM suppresses crossovers in plants by unwinding recombination intermediates. In wheat, crossovers are skewed toward the chromosome ends, thus limiting generation of novel allelic combinations. Here, we observe that FANCM maintains the obligate crossover in tetraploid and hexaploid wheat, thus ensuring that every chromosome pair exhibits at least one crossover, by localizing class I crossover protein HEI10 at pachytene.
View Article and Find Full Text PDFThe cost of microalgae cultivation is one of the largest limitations to achieving sustainable, large-scale microalgae production of commercially desirable lipids. Utilizing CO2 as a 'free' carbon source from waste industrial flue gas emissions can offer wide-ranging cost savings. However, these gas streams typically create acidic environments, in which most microalgae cannot survive due to the concentration of CO2 and the presence of other acidic gasses such as NO2 and SO2.
View Article and Find Full Text PDFObjectives: Anxiety has been associated with childhood abuse/neglect, but this relationship and its mechanisms are poorly documented in older adults. This study examined the association between childhood abuse/neglect and late-life anxiety temporal patterns (i.e.
View Article and Find Full Text PDFBackground: Despite efforts to increase the overall diversity of the medical student body, some medical specialties have a less diverse applicant pool based on both gender and race than would be expected based on medical graduate demographics.
Objectives: To identify whether women and Underrepresented in Medicine (URiM) medical students have baseline differences in their career interests or if their career plans change more during medical school when compared to men and non-URIM students.
Methods: Secondary data analyses of all medical students who applied through ERAS from 2005-2010 was conducted.
For mass culture of photosynthetic green microalgae, industrial flue gases can represent a low-cost resource of CO. However, flue gases are often avoided, because they often also contain high levels of SO and/or NO, which cause significant acidification of media to below pH 3 due to production of sulfuric and nitric acid. This creates an unsuitable environment for the neutrophilic microalgae commonly used in large-scale commercial production.
View Article and Find Full Text PDFPurpose: The objective of this exploratory study was to evaluate the effects of a brief intervention intended to optimize the sleep environment in older people living in the community and to examine the way these effects change over time.
Methods: The sample was made up of 44 participants (19 men and 25 women) aged 65-85 years, with a mean age of 71.4.
Crossovers (COs) ensure accurate chromosome segregation during meiosis while creating novel allelic combinations. Here, we show that allotetraploid (AABB) durum wheat ( ssp. ) utilizes two pathways of meiotic recombination.
View Article and Find Full Text PDFBackground: Radiotherapy and brachytherapy are common treatments for localized prostate cancer (PCa). However, very few studies evaluated the association of variations in DNA damage response genes and treatment outcomes and toxicity in brachytherapy-treated patients.
Purpose: To evaluate the association of inherited germline variations in DNA repair-associated genes with tumor control and treatment toxicity in patients treated with low-dose-rate prostate brachytherapy (LDRB).
CRISPR-Cas9 gene editing provides a powerful tool to enhance the natural ability of human T cells to fight cancer. We report a first-in-human phase 1 clinical trial to test the safety and feasibility of multiplex CRISPR-Cas9 editing to engineer T cells in three patients with refractory cancer. Two genes encoding the endogenous T cell receptor (TCR) chains, TCRα () and TCRβ (), were deleted in T cells to reduce TCR mispairing and to enhance the expression of a synthetic, cancer-specific TCR transgene (NY-ESO-1).
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