919 research outputs found

    Apes communicate about absent and displaced objects: methodology matters

    Get PDF
    Displaced reference is the ability to refer to an item that has been moved (displaced) in space and/or time, and has been called one of the true hallmarks of referential communication. Several studies suggest that nonhuman primates have this capability, but a recent experiment concluded that in a specific situation (absent entities) human infants display displaced reference but chimpanzees do not. Here we show that chimpanzees and bonobos of diverse rearing histories are capable of displaced reference to absent and displaced objects. It is likely that some of the conflicting findings from animal cognition studies are due to relatively minor methodological differences, but are compounded by interpretation errors. Comparative studies are of great importance in elucidating the evolution of human cognition, however, greater care must be taken with methodology and interpretation for these studies to accurately reflect species differences

    Phylogenetic revision of Backhousieae (Myrtaceae): Neogene divergence, a revised circumscription of Backhousia and two new species

    Get PDF
    Backhousieae is a small tribe of Myrtaceae composed of two genera (Backhousia and Choricarpia) endemic to Australia. Phylogenetic analyses (parsimony, maximum likelihood and Bayesian) were performed on a combined chloroplast (matK, trnH–psbA, trnC–psbM, trnL–F, rps16) and nuclear (internal transcribed spacers) dataset for all nine species of Backhousia, two species of Choricarpia and two undescribed species. Backhousieae is monophyletic; however, Choricarpia is embedded within Backhousia. In all analyses there were four strongly supported clades containing two to four taxa, with no support for relationships among clades, and the relationships of B. bancroftii and B. citriodora remain unresolved. Bayesian relaxed-clock molecular dating indicated that the Backhousieae has been potentially present in rainforest across Australia for more than 50 million years. The current distribution of Backhousia is inferred to be largely due to the contraction of Australian rainforest in the Neogene. New combinations in Backhousia are made for the two species of Choricarpia, and B. gundarara and B. tetraptera are described as new species. B. gundarara is known only from the Kimberley region of Western Australia, widely disjunct from the remaining Backhousia in eastern Queensland and New South Wales, and appears to be a lineage isolated by increasing aridity during the Miocene

    Bidirectional lipid droplet velocities are controlled by differential binding strengths of HCV Core DII protein

    Get PDF
    Host cell lipid droplets (LD) are essential in the hepatitis C virus (HCV) life cycle and are targeted by the viral capsid core protein. Core-coated LDs accumulate in the perinuclear region and facilitate viral particle assembly, but it is unclear how mobility of these LDs is directed by core. Herein we used two-photon fluorescence, differential interference contrast imaging, and coherent anti-Stokes Raman scattering microscopies, to reveal novel core-mediated changes to LD dynamics. Expression of core protein’s lipid binding domain II (DII-core) induced slower LD speeds, but did not affect directionality of movement on microtubules. Modulating the LD binding strength of DII-core further impacted LD mobility, revealing the temporal effects of LD-bound DII-core. These results for DII-core coated LDs support a model for core-mediated LD localization that involves core slowing down the rate of movement of LDs until localization at the perinuclear region is accomplished where LD movement ceases. The guided localization of LDs by HCV core protein not only is essential to the viral life cycle but also poses an interesting target for the development of antiviral strategies against HCV

    Changing the Face of an Institution: Creative Partnerships for Women’s Professional Development

    Get PDF
    Purpose of program/study/research:To accelerate the advancement of women professionals at an academic medical center through creative collaboration. Methodology (including study design, analysis, and evaluation):The UMass Medical School Women’s Faculty Committee (WFC) initiated a partnership with the medical library to compete successfully to host the traveling exhibition “Changing the Face of Medicine: Celebrating America’s Women Physicians.” Concurrent with the 6-week exhibition, fifteen events brought local and nationally prominent women together for mentoring activities, an original dramatic production, and an awards luncheon for women faculty. Women featured in the exhibit as well as its Visiting Curator spoke at UMMS about their research and career challenges, read from their published works, and were featured at graduation and a regional medical society event. Results:Application-writing and event planning sessions forged robust working relationships among top-ranking administrators, senior and junior faculty, and staff. The exhibition increased opportunities for administration, faculty, and students to understand the impact of women in medicine, their leadership potential, and historical contributions. It also generated new mentor/mentee relationships and grant-writing collaborations. The exhibition’s national recognition helped draw a larger, more diverse and gender-balanced audience (575+ people) to the events enhancing the visibility of the WFC, as evidenced by institutional funding for women faculty to attend the AAMC WIM professional development workshops and ELAM for the first time. Conclusion(s):Creative partnerships, motivated by the opportunity to host “Changing the Face of Medicine,” produced greater than expected gains for women faculty, generating new awareness and understanding of women’s accomplishments and leadership potential. This partnership allowed for a wide range of multi-disciplinary efforts, strengthening networking across silos, and advancing the goals of women in an academic medical center. Presented October 29, 2006 at AAMC 2006 Annaul Meeting, Seattle, WA

    An ordinary differential equation for velocity distribution and dip-phenomenon in open channel flows

    Full text link
    An ordinary differential equation for velocity distribution in open channel flows is presented based on an analysis of the Reynolds-Averaged Navier-Stokes equations and a log-wake modified eddy viscosity distribution. This proposed equation allows to predict the velocity-dip-phenomenon, i.e. the maximum velocity below the free surface. Two different degrees of approximations are presented, a semi-analytical solution of the proposed ordinary differential equation, i.e. the full dip-modified-log-wake law and a simple dip-modified-log-wake law. Velocity profiles of the two laws and the numerical solution of the ordinary differential equation are compared with experimental data. This study shows that the dip correction is not efficient for a small Coles' parameter, accurate predictions require larger values. The simple dip-modified-log-wake law shows reasonable agreement and seems to be an interesting tool of intermediate accuracy. The full dip-modified-log-wake law, with a parameter for dip-correction obtained from an estimation of dip positions, provides accurate velocity profiles

    Predicted Infrared and Raman Spectra for Neutral Ti_8C_12 Isomers

    Full text link
    Using a density-functional based algorithm, the full IR and Raman spectra are calculated for the neutral Ti_8C_12 cluster assuming geometries of Th, Td, D2d and C3v symmetry. The Th pentagonal dodecahedron is found to be dynamically unstable. The calculated properties of the relaxed structure having C3v symmetry are found to be in excellent agreement with experimental gas phase infrared results, ionization potential and electron affinity measurements. Consequently, the results presented may be used as a reference for further experimental characterization using vibrational spectroscopy.Comment: 6 pages, 5 figures. Physical Review A, 2002 (in press

    Incident Heart Failure Is Associated with Lower Whole-Grain Intake and Greater High-Fat Dairy and Egg Intake in the Atherosclerosis Risk in Communities (ARIC) Study

    Get PDF
    Prospective studies evaluating associations between food intake and risk of heart failure (HF) in diverse populations are needed

    A prospective evaluation of the predictive value of faecal calprotectin in quiescent Crohn’s disease

    Get PDF
    Background: The faecal calprotectin (FC) test is a non-invasive marker for gastrointestinal inflammation. Aim: To determine whether higher FC levels in individuals with quiescent Crohn’s disease are associated with clinical relapse over the ensuing 12 months.<p></p> Methods: A single centre prospective study was undertaken in Crohn's disease patients in clinical remission attending for routine review. The receiver operating characteristic (ROC) curve for the primary endpoint of clinical relapse by 12 months, based on FC at baseline, was calculated. Kaplan-Meier curves of time to relapse were based on the resulting optimal FC cutoff for predicting relapse.<p></p> Results: Of 97 patients recruited, 92 were either followed up for 12 months without relapsing, or reached the primary endpoint within that period. Of these, 10 (11%) had relapsed by 12 months. The median FC was lower for non-relapsers, 96”g/g (IQR 39-237), than for relapsers, 414”g/g (IQR 259-590), (p=0.005). The area under the ROC curve to predict relapse using FC was 77.4%. An optimal cutoff FC value of 240”g/g to predict relapse of quiescent Crohn’s had sensitivity of 80.0% and specificity of 74.4%. Negative predictive value was 96.8% and positive predictive value was 27.6%. FC≄240ÎŒg/g was associated with likelihood of relapse 5.7 (95% CI 1.9-17.3) times higher within 2.3 years than lower values (p=0.002).<p></p> Conclusions: In this prospective dataset, FC appears to be a useful, non-invasive tool to help identify quiescent Crohn’s disease patients at a low risk of relapse over the ensuing 12 months. FC of 240”g/g was the optimal cutoff in this cohort.<p></p&gt
    • 

    corecore