Who doesn't receive carotid endarterectomy when appropriate?

AbstractObjectiveThe purpose of this study was to identify clinical and nonclinical factors associated with failure to perform carotid endarterectomy (CEA) in patients with clinically appropriate indications. We analyzed data from a prospective cohort study performed at five Veterans Affairs medical centers. Patients were referred for carotid artery evaluation if they had at least 50% stenosis in one carotid artery, had no history of CEA, and were independently classified preoperatively as appropriate candidates for CEA, according to clinical criteria. The primary outcome was receipt of CEA within 6 months of evaluation. Data were collected by medical record review and interview regarding clinical status, and patient and physician perception of the risks and benefits of CEA.ResultsAmong clinically appropriate candidates for CEA, 66.8% (n = 233) did not undergo the operation. Compared with patients who did undergo CEA, a greater proportion of these patients had no symptoms (68.7% vs 45.7%; P < .001). A twofold greater proportion of patients who did not undergo CEA were in the highest quartile of reported aversion to surgery. Moreover, a fourfold greater proportion were perceived by their physicians to be at less than 5% risk for future stroke without the operation, and more than a twofold greater proportion were believed to experience less than 5% efficacy from the operation by their providers (P < .01). In multivariable analyses, four characteristics were significantly associated with whether an appropriate candidate did not receive CEA: asymptomatic disease, less than 70% stenosis, high expressed aversion to surgery score, and low (<5%) provider-perceived efficacy of the operation.ConclusionAmong patients in the Veterans Affairs health care system who are clinically appropriate candidates for CEA, those who did not receive the operation were less likely to have symptomatic disease or high-grade carotid artery stenosis, but were more likely to report high aversion to surgery and to have a provider who believed CEA would not be efficacious

Transmission of Multiple Traditions within and between Chimpanzee Groups

SummaryField reports provide increasing evidence for local behavioral traditions among fish, birds, and mammals [1–7]. These findings are significant for evolutionary biology because social learning affords faster adaptation than genetic change and has generated new (cultural) forms of evolution [8–10]. Orangutan and chimpanzee field studies [3, 4, 11–13] suggest that like humans [14, 15], these apes are distinctive among animals in each exhibiting over 30 local traditions. However, direct evidence is lacking in apes and, with the exception of vocal dialects [16, 17], in animals generally for the intergroup transmission that would allow innovations to spread widely and become evolutionarily significant phenomena. Here, we provide robust experimental evidence that alternative foraging techniques seeded in different groups of chimpanzees spread differentially not only within groups but serially across two further groups with substantial fidelity. Combining these results with those from recent social-diffusion studies in two larger groups [18–20] offers the first experimental evidence that a nonhuman species can sustain unique local cultures, each constituted by multiple traditions. The convergence of these results with those from the wild implies a richness in chimpanzees' capacity for culture, a richness that parsimony suggests was shared with our common ancestor

Neural evidence of deprioritizing to-be-forgotten information in visual working memory

IntroductionAlthough evidence supports the effective use of a cue to forget an encoded stimulus, the mechanisms of this forgetting are not well understood. Evidence from item-method directed forgetting in long-term memory reveals greater prefrontal and parietal activation for information that is cued to be forgotten. Activation in those brain regions is typically associated with increased effort and cognitive control.MethodTo test the mechanism of directed forgetting in visual working memory, we used stimuli that rely on distinct brain regions such as faces and buildings and varied memory stability. Participants completed a directed forgetting task with faces and buildings, and memory stability was manipulated by presenting some stimuli repeatedly throughout the study, and other stimuli were only presented once.Results and discussionFunctional magnetic resonance imaging (fMRI) results from the parahippocampal place area suggest that to-be-remembered buildings elicit higher activation than to-be-forgotten buildings. In addition, dorsolateral prefrontal cortex activation changed throughout the trial period, possibly suggesting that the cue led to information being dropped from visual working memory, or through a shift in attention, as occurs with the retro-cue paradigm. Several explanations for these results are discussed

On the response of a buoyant plume to downwelling-favorable wind stress

Author Posting. © American Meteorological Society, 2012. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Journal of Physical Oceanography 42 (2012): 1083–1098, doi:10.1175/JPO-D-11-015.1.Here, the response of a coastally trapped buoyant plume to downwelling-favorable wind forcing is explored using a simplified two-dimensional numerical model and a prognostic theory for the resulting width, depth, and density anomaly and along-shelf transport of the plume. Consistent with the numerical simulations, the analytical model shows that the wind causes mixing of the plume water and that the forced cross-shelf circulation can also generate significant deepening and surface narrowing, as well as increased along-shelf transport. The response is due to a combination of the purely advective process that leads to the steepening of the isopycnals and the entrainment of ambient water into the plume. The advective component depends on the initial plume geometry: plumes that have a large fraction of their total width in contact with the bottom (“bottom trapped”) suffer relatively small depth and width changes compared to plumes that have a large fraction of their total width detached from the bottom (“surface trapped”). Key theoretical parameters are Wγ/Wα, the ratio of the width of the plume detached from the bottom to the width of the plume in contact with it, and the ratio of the wind-generated mixed layer δe to the initial plume depth hp, which determines the amount of water initially entrained into the plume. The model results also show that the cross-shelf circulation can be strongly influenced by the wind-driven response in combination with the geostrophic shear of the plume. The continuous entrainment into the plume, as well as transient events, is also discussed.This work has been supported by FONDECYT Grant 1070501. S. Lentz received support by theNational Science Foundation GrantOCE-0751554. C. Moffat had additional support from the National Science Foundation Office of Polar Programs through U.S. Southern Ocean GLOBEC Grants OPP 99-10092 and 06- 23223.2013-01-0

The Lantern Vol. 16, No. 2, December 1947

• A Little Light • Traitor\u27s Son • The Comeback • Wolf-Dog • Lucky Harry • Security or Progress • To Tell a Story • Endless • What Purpose, Life? • I Would Not Say • Adult Farewell • Springtime Fields • M.W. Armstronghttps://digitalcommons.ursinus.edu/lantern/1044/thumbnail.jp

Common Avian Infection Plagued the Tyrant Dinosaurs

Abstract Background: Tyrannosaurus rex and other tyrannosaurid fossils often display multiple, smooth-edged full-thickness erosive lesions on the mandible, either unilaterally or bilaterally. The cause of these lesions in the Tyrannosaurus rex specimen FMNH PR2081 (known informally by the name &apos;Sue&apos;) has previously been attributed to actinomycosis, a bacterial bone infection, or bite wounds from other tyrannosaurids