919 research outputs found
Apes communicate about absent and displaced objects: methodology matters
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
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, trnHâpsbA, trnCâpsbM, trnLâF, 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
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 proteinâs 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 Womenâs Professional Development
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 Womenâs Faculty Committee (WFC) initiated a partnership with the medical library to compete successfully to host the traveling exhibition âChanging the Face of Medicine: Celebrating Americaâs Women Physicians.â 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 exhibitionâs 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 âChanging the Face of Medicine,â produced greater than expected gains for women faculty, generating new awareness and understanding of womenâs 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
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
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Assessing the comparative effectiveness of Tai Chi versus physical therapy for knee osteoarthritis: design and rationale for a randomized trial
Background: Knee osteoarthritis (OA) causes pain and long-term disability with annual healthcare costs exceeding $185 billion in the United States. Few medical remedies effectively influence the course of the disease. Finding effective treatments to maintain function and quality of life in patients with knee OA is one of the national priorities identified by the Institute of Medicine. We are currently conducting the first comparative effectiveness and cost-effectiveness randomized trial of Tai Chi versus a physical-therapy regimen in a sample of patients with symptomatic and radiographically confirmed knee OA. This article describes the design and conduct of this trial. Methods/Design A single-center, 52-week, comparative effectiveness randomized controlled trial of Tai Chi versus a standardized physical-therapy regimen is being conducted at an urban tertiary medical center in Boston, Massachusetts. The study population consists of adults â„ 40 years of age with symptomatic and radiographic knee OA (American College of Rheumatology criteria). Participants are randomly allocated to either 12 weeks of Tai Chi (2x/week) or Physical Therapy (2x/week for 6 weeks, followed by 6 weeks of rigorously monitored home exercise). The primary outcome measure is pain (Western Ontario and McMaster Universities WOMAC) subscale at 12 weeks. Secondary outcomes include WOMAC stkiffness and function domain scores, lower extremity strength and power, functional balance, physical performance tests, psychological and psychosocial functioning, durability effects, health related quality of life, and healthcare utilization at 12, 24 and 52 weeks. Discussion This study will be the first randomized comparative-effectiveness and cost-effectiveness trial of Tai Chi versus Physical Therapy in a large symptomatic knee OA population with long-term follow up. We present here a robust and well-designed randomized comparative-effectiveness trial that also explores multiple outcomes to elucidate the potential mechanisms of mind-body effect for a major disabling disease with substantial health burdens and economic costs. Results of this study are expected to have important public health implications for the large and growing population with knee OA. Trial registration ClinicalTrials.gov identifier: NCT01258985 Electronic supplementary material The online version of this article (doi:10.1186/1472-6882-14-333) contains supplementary material, which is available to authorized users
Predicted Infrared and Raman Spectra for Neutral Ti_8C_12 Isomers
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
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 Crohnâs disease
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 Crohnâs 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 Crohnâs had sensitivity of 80.0% and specificity of 74.4%. Negative predictive value was 96.8% and positive predictive value was 27.6%. FCâ„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 Crohnâs 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>
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