537 research outputs found
Stress Tensor Perturbations in Conformal Field Theory
We reconsider the problem of deforming a conformal ļ¬eld theory to a neighboring theory which is again critical. An invariant formulation of this problem is important for understanding the underlying symmetry of string theory. We give a simple derivation of A. Senās recent formula for the change in the stress tensor and show that, when correctly interpreted, it is coordinate-invariant. We give the corresponding superconformal perturbation for superļ¬eld backgrounds and explain why it has no direct analog for spin-ļ¬eld backgrounds
Norton Healthcare: A Strong Payer-Provider Partnership for the Journey to Accountable Care
Examines the progress of an integrated healthcare delivery system in forming an accountable care organization with payer partners as part of the Brookings-Dartmouth ACO Pilot Program, including a focus on performance measurement and reporting
A Longitudinal Study of Hospitalization Rates for Patients with Chronic Disease: Results from the Medical Outcomes Study.
To prospectively compare inpatient and outpatient utilization rates between prepaid (PPD) and fee-for-service (FFS) insurance coverage for patients with chronic disease. Data from the Medical Outcomes Study, a longitudinal observational study of chronic disease patients conducted in Boston, Chicago, and Los Angeles.A four-year prospective study of resource utilization among 1,681 patients under treatment for hypertension, diabetes, myocardial infarction, or congestive heart failure in the practices of 367 clinicians
Health Care Delivery Practices inĀ Huntington's Disease Specialty Clinics : AnĀ International Survey
The CHDI Foundation, Inc. funds Enroll-HD and the activities of the Enroll-HD Care Improvement Committee, including the present survey. We would like to acknowledge the Enroll-HD and REGISTRY administrative staff that assisted in the recruitment of sites and sites that completed the survey.Peer reviewedPublisher PD
HealthCare Partners: Building on a Foundation of Global Risk Management to Achieve Accountable Care
Describes the progress of a medical group and independent practice association in forming an accountable care organization by working with insurers as part of the Brookings-Dartmouth ACO Pilot Program. Lists lessons learned and elements of success
Four Health Care Organizations' Efforts to Improve Patient Care and Reduce Costs
Synthesizes findings from four case studies in the Brookings-Dartmouth ACO Pilot Program about forming integrated systems that can deliver accountable care under shared-savings agreements with private payers
A central role for microvillous receptor presentation in leukocyte adhesion under flow
AbstractLeukocyte adhesion to endothelium requires specialized mechanisms for contact initiation under flow. L-selectin (CD62L), an efficient initiator of adhesion, is clustered on the tips of leukocyte microvilli. To test whether microvillous presentation is critical for contact formation (ātetheringā), we transfected lymphoid cells with chimeras of L-selectin and CD44, an adhesion molecule that is excluded from microvilli. CD44 transmembrane and intracellular (TM-IC) domains targeted the L-selectin ectodomain to the planar body, whereas L-selectin TM-IC segments conferred CD44 ectodomain clustering on microvilli. Wild-type and chimeric transfectants bound similarly to anti-ectodomain MAbs in static assays, but MAb binding under flow was much more efficient in the context of microvillous presentation. Similarly, wild-type and chimeric L-selectin possessed equivalent lectin activity, but microvillous presentation dramatically enhanced contact initiation on a native ligand. These findings demonstrate a critical role for receptor topography in leukocyte adhesion and suggest a novel regulatory mechanism of leukocyte trafficking
Early antenatal prediction of gestational diabetes in obese women: development of prediction tools for targeted intervention
All obese women are categorised as being of equally high risk of gestational diabetes (GDM) whereas the majority do not develop the disorder. Lifestyle and pharmacological interventions in unselected obese pregnant women have been unsuccessful in preventing GDM. Our aim was to develop a prediction tool for early identification of obese women at high risk of GDM to facilitate targeted interventions in those most likely to benefit. Clinical and anthropometric data and non-fasting blood samples were obtained at 15+0ā18+6 weeksā gestation in 1303 obese pregnant women from UPBEAT, a randomised controlled trial of a behavioural intervention. Twenty one candidate biomarkers associated with insulin resistance, and a targeted nuclear magnetic resonance (NMR) metabolome were measured. Prediction models were constructed using stepwise logistic regression. Twenty six percent of women (n = 337) developed GDM (International Association of Diabetes and Pregnancy Study Groups criteria). A model based on clinical and anthropometric variables (age, previous GDM, family history of type 2 diabetes, systolic blood pressure, sum of skinfold thicknesses, waist:height and neck:thigh ratios) provided an area under the curve of 0.71 (95%CI 0.68ā0.74). This increased to 0.77 (95%CI 0.73ā0.80) with addition of candidate biomarkers (random glucose, haemoglobin A1c (HbA1c), fructosamine, adiponectin, sex hormone binding globulin, triglycerides), but was not improved by addition of NMR metabolites (0.77; 95%CI 0.74ā0.81). Clinically translatable models for GDM prediction including readily measurable variables e.g. mid-arm circumference, age, systolic blood pressure, HbA1c and adiponectin are described. Using a ā„35% risk threshold, all models identified a group of high risk obese women of whom approximately 50% (positive predictive value) later developed GDM, with a negative predictive value of 80%. Tools for early pregnancy identification of obese women at risk of GDM are described which could enable targeted interventions for GDM prevention in women who will benefit the most
Validation of a New Predictive Risk Model: Measuring the Impact of the Major Modifiable Risks of Death for Patients and Populations
Background: Modifiable risks account for a large fraction of disease and death, but clinicians and patients lack tools to identify high risk populations or compare the possible benefit of different interventions.
Methods: We used data on the distribution of exposure to 12 major behavioral and biometric risk factors inthe US population, mortality rates by cause, and estimates of the proportional hazards of risk factor exposure from published systematic reviews to develop a risk prediction model that estimates an adult\u27s 10 year mortality risk compared to a population with optimum risk factors. We compared predicted risk to observed mortality in 8,241 respondents in NHANES 1988-1994 and NHANES 1999-2004 with linked mortality data up to the end of 2006
Dispersity-Driven Melting Transition in Two Dimensional Solids
We perform extensive simulations of Lennard-Jones particles to study
the effect of particle size dispersity on the thermodynamic stability of
two-dimensional solids. We find a novel phase diagram in the dispersity-density
parameter space. We observe that for large values of the density there is a
threshold value of the size dispersity above which the solid melts to a liquid
along a line of first order phase transitions. For smaller values of density,
our results are consistent with the presence of an intermediate hexatic phase.
Further, these findings support the possibility of a multicritical point in the
dispersity-density parameter space.Comment: In revtex format, 4 pages, 6 postscript figures. Submitted to PR
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