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Non-fibrillar soluble oligomeric forms of amyloid-β peptide (oAβ) and tau proteins are likely to play a major role in Alzheimer’s disease (AD). The prevailing hypothesis on the disease etiopathogenesis is that oAβ initiates tau pathology that slowly spreads throughout the medial temporal cortex and neocortices independently of Aβ, eventually leading to memory loss. Here we show that a brief exposure to extracellular recombinant human tau oligomers (oTau), but not monomers, produces an impairment of long-term potentiation (LTP) and memory, independent of the presence of high oAβ levels. The impairment is immediate as it raises as soon as 20 min after exposure to the oligomers. These effects are reproduced either by oTau extracted from AD human specimens, or naturally produced in mice overexpressing human tau. Finally, we found that oTau could also act in combination with oAβ to produce these effects, as sub-toxic doses of the two peptides combined lead to LTP and memory impairment. These findings provide a novel view of the effects of tau and Aβ on memory loss, offering new therapeutic opportunities in the therapy of AD and other neurodegenerative diseases associated with Aβ and tau pathology.

Selection causes local adaptation across populations within species and simultaneously divergence between species. However, it is unclear if either the force of or the response to selection is similar across these scales. We show that natural selection drives divergence between closely related species in a pattern that is distinct from local adaptation within species. We use reciprocal transplant experiments across three species of Phlox wildflowers to characterize widespread adaptive divergence. Using provenance trials, we also find strong local adaptation between populations within a species. Comparing divergence and selection between these two scales of diversity we discover that one suite of traits predicts fitness differences between species and that an independent suite of traits predicts fitness variation within species. Selection drives divergence between species, contributing to speciation, while simultaneously favoring extensive diversity that is maintained across populations within a species. Our work demonstrates how the selection landscape is complex and multidimensional. Selection drives divergence between species, contributing to speciation, while simultaneously favoring extensive diversity that is maintained across populations within a species. This study demonstrates how the selection landscape is complex and multidimensional across three species of Phlox flowers.

\"In Mapping and Navigation: the history and science of finding your way, kids ages 9-12 will learn the history and science behind the evolution of mapmaking, and how much is still out there for discovery. Readers will explore ideas through hands-on-experiments while learning new terminology and interesting facts. Projects include using triangulation to measure distances, creating contour lines on a mini-mountain to understand elevation changes on a map, and inventing a sundial and compass to understand the basics of navigation. Whether mapping the solar system or mapping their own backyard, all readers will be able to understand mapping technologies and see the world in new and exciting ways.\"--Publisher's description.

H. pylori is a common bacterium, and approximately 50 percent of the world's population has been estimated to be infected (198). Humans are the principal reservoir. The prevalence of H. pylori infection varies widely by geographic area, age, race, ethnicity, and SES. Rates appear to be higher in developing than in developed countries, with most of the infections occurring during childhood, and they seem to be decreasing with improvements in hygiene practices. H. pylori causes chronic gastritis and has been associated with several serious diseases of the gastrointestinal tract, including duodenal ulcer and gastric cancer. Since its \"discovery\" in 1982 by Warren and Marshall (1), H. pylori has been the topic of extensive research. A number of studies have used questionnaire components to investigate factors possibly related to the etiology of H. pylori infection. The majority of recent studies have not found tobacco use or alcohol consumption to be risk factors for H. pylori infection. Adequate nutritional status, especially frequent consumption of fruits and vegetables and of vitamin C, appears to protect against infection with H. pylori. In contrast, food prepared under less than ideal conditions or exposed to contaminated water or soil may increase the risk. Overall, inadequate sanitation practices, low social class, and crowded or high-density living conditions seem to be related to a higher prevalence of H. pylori infection. This finding suggests that poor hygiene and crowded conditions may facilitate transmission of infection among family members and is consistent with data on intrafamilial and institutional clustering of H. pylori infection. Understanding the route of H. pylori transmission is important if public health measures to prevent its spread are to be implemented. Iatrogenic transmission of H. pylori following endoscopy is the only proven mode. For the general population, the most likely mode of transmission is from person to person, by either the oral-oral route (through vomitus or possibly saliva) or perhaps the fecal-oral route. The person-to-person mode of transmission is supported by the higher incidence of infection among institutionalized children and adults and the clustering of H. pylori infection within families. Also lending support to this concept is the detection of H. pylori DNA in vomitus, saliva, dental plaque, gastric juice, and feces. Waterborne transmission, probably due to fecal contamination, may be an important source of infection, especially in parts of the world in which untreated water is common. Recent studies in the United States have linked clinical H. pylori infection with consumption of H. pylori-contaminated well water. This area of research is worthy of further investigation. Although H. pylori has been isolated in domestic cats, additional research has suggested that H. pylori is probably uncommon in domestic cats and thus is probably not a major concern for cat owners. Several studies have suggested sheep as a possible source of H. pylori transmission, a hypothesis that deserves additional investigation. The most recent reservoir suggested for H. pylori transmission is the housefly. However, evidence is lacking that H. pylori can be transmitted to humans from flies that have been in contact with H. pylori-infected feces. Nevertheless, the hypothesis is appealing since flies are known to carry many other infectious diseases. Knowledge of the epidemiology and mode of transmission of H. pylori is important to prevent its spread and may be useful in identifying high-risk populations, especially in areas that have high rates of gastric lymphoma, gastric cancer, and gastric ulcer.

\"Alonso Berruguete (c. 1488-1561) revolutionized the arts of Renaissance Spain with a dramatic style of sculpture that reflected the decade or more he had spent in Italy while young. Trained as a painter, he traveled to Italy around 1506, where he interacted with Michelangelo and other leading artists. In 1518, he returned to Spain and was appointed court painter to the new king, Charles I. Eventually, he made his way to Valladolid, where he shifted his focus to sculpture, opening a large workshop that produced breathtaking multistory altarpieces (retablos) decorated with sculptures in painted wood. This handsomely illustrated catalogue is the first in English to treat Berruguete's art and career comprehensively. It follows his career from his beginnings in Castile to his final years in Toledo, where he produced his last great work, the marble tomb of Cardinal Juan de Tavera. Enriching the chronological narrative are discussions of important aspects of Berruguete's life and practice: his complicated relationship with social status and wealth; his activity as a draftsman and use of prints; how he worked with his many assistants to create his wood sculptures; and his legacy as an artist\"-- Provided by publisher.

The sand tiger shark Carcharias taurus is a highly migratory coastal species with declining populations worldwide. This species exhibits many behaviors that make coastal sharks difficult to manage, including aggregatory behavior, sexual segregation, and large-scale migrations through shallow coastal waters with many opportunities for human interactions. Sand tigers from the Western North Atlantic subpopulation are known to seasonally inhabit Delaware Bay and surrounding coastal waters. This region has been recommended as a habitat area of particular concern for the Western North Atlantic sand tiger population, and increased understanding of their movements and habitat requirements will facilitate management efforts. We developed models to predict sand tiger occupancy using spatially dynamic environmental predictors. Our models predicted sand tiger (juveniles, adult males, adult females, and all sharks combined) occurrences in 2 study regions, the Delaware Bay and the western Mid-Atlantic coastal ocean. Sea surface temperature, day of year, water depth, and remote sensing reflectance at 555 nm were the most important environmental predictors of occurrence, and correctly predicted 80–89% of sand tiger acoustic telemetry records in the 2 study regions. Our models predicted differences in the timing and location of occurrences among juveniles and adults, as well as areas where these life history stages overlap in the Mid-Atlantic coastal ocean. Our hope is that a daily forecast of sand tiger occurrence from our modeling efforts could be useful for conservation and management efforts in this important region, as well as for studying the spatial and behavioral ecology of this important top predator.

The role of feminist theory in health professions education is often ‘ova-looked’. Gender is one cause of healthcare inequalities within contemporary medicine. Shockingly, according to the World Health Organisation, no European member state has achieved full gender equity in regard to health outcomes. Further, contemporary curricula have not evolved to reflect the realities of a diverse society that remains riddled with inequity. This paper outlines the history of feminist theory, and applies it to health professions education research and teaching, in order to advocate for its continued relevance within contemporary healthcare.

Background The testing of theoretical models with experimental data is an integral part of the scientific method, and a logical place to search for new ways of stimulating scientific productivity. Often experiment/theory comparisons may be viewed as a workflow comprised of well-defined, rote operations distributed over several distinct computers, as exemplified by the way in which predictions from electronic structure theories are evaluated with results from spectroscopic experiments. For workflows such as this, which may be laborious and time consuming to perform manually, software that could orchestrate the operations and transfer results between computers in a seamless and automated fashion would offer major efficiency gains. Such tools also promise to alter how researchers interact with data outside their field of specialization by, e.g., making raw experimental results more accessible to theorists, and the outputs of theoretical calculations more readily comprehended by experimentalists. Results An implementation of an automated workflow has been developed for the integrated analysis of data from nuclear magnetic resonance (NMR) experiments and electronic structure calculations. Kepler (Altintas et al. 2004 ) open source software was used to coordinate the processing and transfer of data at each step of the workflow. This workflow incorporated several open source software components, including electronic structure code to compute NMR parameters, a program to simulate NMR signals, NMR data processing programs, and others. The Kepler software was found to be sufficiently flexible to address several minor implementation challenges without recourse to other software solutions. The automated workflow was demonstrated with data from a 17 O NMR study of uranyl salts described previously (Cho et al. in J Chem Phys 132:084501, 2010 ). Conclusions The functional implementation of an automated process linking NMR data with electronic structure predictions demonstrates that modern software tools such as Kepler can be used to construct programs that comprehensively manage complex, multi-step scientific workflows spanning several different computers. Automation of the workflow can greatly accelerate the pace of discovery, and allows researchers to focus on the fundamental scientific questions rather than mastery of specialized software and data processing techniques. Future developments that would expand the scope and power of this approach include tools to standardize data and associated metadata formats, and the creation of interactive user interfaces to allow real-time exploration of the effects of program inputs on calculated outputs.