The orientation of swimming bi-flagellates in shear flows

Biflagellated algae swim in mean directions that are governed by their environments. For example, many algae can swim upward on average (gravitaxis) and toward downwelling fluid (gyrotaxis) via a variety of mechanisms. Accumulations of cells within the fluid can induce hydrodynamic instabilities leading to patterns and flow, termed bioconvection, which may be of particular relevance to algal bioreactors and plankton dynamics. Furthermore, knowledge of the behavior of an individual swimming cell subject to imposed flow is prerequisite to a full understanding of the scaled-up bulk behavior and population dynamics of cells in oceans and lakes; swimming behavior and patchiness will impact opportunities for interactions, which are at the heart of population models. Hence, better estimates of population level parameters necessitate a detailed understanding of cell swimming bias. Using the method of regularized Stokeslets, numerical computations are developed to investigate the swimming behavior of and fluid flow around gyrotactic prolate spheroidal biflagellates with five distinct flagellar beats. In particular, we explore cell reorientation mechanisms associated with bottom-heaviness and sedimentation and find that they are commensurate and complementary. Furthermore, using an experimentally measured flagellar beat for Chlamydomonas reinhardtii, we reveal that the effective cell eccentricity of the swimming cell is much smaller than for the inanimate body alone, suggesting that the cells may be modeled satisfactorily as self-propelled spheres. Finally, we propose a method to estimate the effective cell eccentricity of any biflagellate when flagellar beat images are obtained haphazardly

Vermont's Choices for Care Medicaid Long-Term Services Waiver: Progress and Challenges as the Program Concluded Its Third Year

Based on case study interviews and state data, evaluates the impact of a waiver introduced in 2005 to improve Medicaid beneficiaries' access to home and community-based services while reducing the use of nursing home care and controlling costs

A Snapshot of U.S. Physicians: Key Findings From the 2008 Health Tracking Physician Survey

Analyzes survey data on U.S. physicians' compensation system, career satisfaction, acceptance of new patients, managed care contracts, and charity care provision by demographics, type of practice, specialty, geographic location, and other characteristics

Nonnegative/binary matrix factorization with a D-Wave quantum annealer

D-Wave quantum annealers represent a novel computational architecture and have attracted significant interest, but have been used for few real-world computations. Machine learning has been identified as an area where quantum annealing may be useful. Here, we show that the D-Wave 2X can be effectively used as part of an unsupervised machine learning method. This method can be used to analyze large datasets. The D-Wave only limits the number of features that can be extracted from the dataset. We apply this method to learn the features from a set of facial images

Making Medical Homes Work: Moving From Concept to Practice

Explores practical considerations for implementing a medical home program of physician practices committed to coordinating and integrating care based on patient needs and priorities, such as how to qualify medical homes and how to match patients to them

Coordination of Care by Primary Care Practices: Strategies, Lessons and Implications

Documents successful strategies for coordinating care within primary care settings, including family and caregivers; with specialists; with hospital settings; and with community-based services. Discusses challenges, lessons learned, and implications

Implementation of Physician Orders for Life Sustaining Treatment in nursing homes in California: evaluation of a novel statewide dissemination mechanism.

BackgroundImplementing Physician Orders for Life Sustaining Treatment (POLST) forms aims to improve communication of life-sustaining treatment preferences across care venues. California enabled this clinical tool in 2009, and a novel intervention of community coalitions was undertaken to advance POLST in localities around the state. Coalitions engaged facilities, including nursing homes (NHs), to foster POLST adoption. Eighteen months after introduction of POLST, we studied POLST implementation in California NHs.MethodsNHs randomly selected in coalition and non-coalition areas were mailed surveys about POLST preparation and use in 2010. Coalitions identified which NHs they worked with.ResultsOf 546 NHs surveyed, 143 (52 %) in coalition areas and 141 (52 %) in non-coalition areas responded. In 82 % of responding NHs, staff received POLST education and 59 % of NHs reported having a formal policy on handling POLST. Two-thirds of NHs had admitted a resident with a POLST, and 15 % of newly admitted residents over the past month had a POLST (range 0-100 %). Eighty-one percent of NHs had completed a POLST with a resident. Fifty-four percent of residents were estimated to have a POLST (range 0-100 %) (coalition area NHs 60 % vs. non- coalition area NHs 48 %, p = 0.02). Within coalition areas, NHs that had worked with coalitions were more likely to have completed a POLST with a resident after admission than NHs that had not worked with coalitions. Few NHs (7 %) reported difficulty following POLST orders, but 38 % noted difficulty involving physicians in POLST completion.ConclusionLess than 2 years after introduction, many California nursing homes report using POLST, although some NHs reported no experience. A novel community coalition intervention facilitated POLST implementation