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Context. The wind-driven halo is a feature that is observed in images that were delivered by the latest generation of ground-based instruments that are equipped with an extreme adaptive optics system and a coronagraphic device, such as SPHERE at the Very Large Telescope (VLT). This signature appears when the atmospheric turbulence conditions vary faster than the adaptive optics loop can correct for. The wind-driven halo is observed as a radial extension of the point spread function along a distinct direction (this is sometimes referred to as the butterfly pattern). When this is present, it significantly limits the contrast capabilities of the instrument and prevents the extraction of signals at close separation or extended signals such as circumstellar disks. This limitation is consequential because it contaminates the data for a substantial fraction of the time: about 30% of the data produced by the VLT/SPHERE instrument are affected by the wind-driven halo. Aims. This paper reviews the causes of the wind-driven halo and presents a method for analyzing its contribution directly from the scientific images. Its effect on the raw contrast and on the final contrast after post-processing is demonstrated. Methods. We used simulations and on-sky SPHERE data to verify that the parameters extracted with our method can describe the wind-driven halo in the images. We studied the temporal, spatial, and spectral variation of these parameters to point out its deleterious effect on the final contrast. Results. The data-driven analysis we propose provides information to accurately describe the wind-driven halo contribution in the images. This analysis confirms that this is a fundamental limitation of the finally reached contrast performance. Conclusions. With the established procedure, we will analyze a large sample of data delivered by SPHERE in order to propose post-processing techniques that are tailored to removing the wind-driven halo.

ObjectivesAlthough care coordination is an essential component of the patient-centered medical home structure, current case manager models have limited usefulness to population health because they typically serve a small group of patients defined based on disease or utilization. Our objective was to support our health system's population health by implementing and evaluating a program that embedded nonlicensed coordinators within our primary care practices to support physicians in executing care plans and communicating with patients.Study designMatched case-control differences-in-differences.MethodsComprehensive care coordinators (CCC) were introduced into 14 of the system's 28 practice sites in 2 waves. After a structured training program, CCCs identified, engaged, and intervened among patients within the practice in conjunction with practice primary care providers. We counted and broadly coded CCC activities that were documented in the intervention database. We examined the impact of CCC intervention on emergency department (ED) utilization at the practice level using a negative binomial multivariate regression model controlling for age, gender, and medical complexity.ResultsCCCs touched 10,500 unique patients over a 1-year period. CCC interventions included execution of care (38%), coordination of transitions (32%), self-management support/link to community resources (15%), monitor and follow-up (10%), and patient assessment (1%). The CCC intervention group had a 20% greater reduction in its prepost ED visit rate compared with the control group (P < .0001).ConclusionsOur CCC intervention demonstrated a significant reduction in ED visits by focusing on the centrality of the primary care provider and practice. Our model may serve as a cost-effective and scalable alternative for care coordination in primary care.

© 2013, Springer Science+Business Media New York. South Asians are disproportionately impacted by cardiovascular disease (CVD). Our objective was to examine the association between duration of residence in the US and CVD risk factors among South Asian adult immigrants. Multivariate logistic regression analyses using pooled data from the 2005, 2007, 2009 California Health Interview Surveys. Duration of residence in the US < 15 years was significantly associated with overweight/obese BMI (OR 0.59; 95 % CI 0.35, 0.98 for 5 to < 10 years), daily consumption of 5+ servings of fruits/vegetables (OR 0.37; 95 % CI 0.15, 0.94 for 10 to < 15 years), and sedentary lifestyle (OR 2.11; 95 % CI 1.17, 3.81 for 10 to < 15 years) compared with duration of residence ≥15 years after adjusting for illness burden, healthcare access, and socio-demographic characteristics. Duration of residence was not significantly associated with other CVD risk factors. Duration of residence is an important correlate of overweight/obesity and other risk factors among South Asian immigrants.

The Durham High-order Demonstrator (DHD) is a proposed high-order/extreme adaptive optics instrument design for the 4.2m William Herschel Telescope on La Palma, Canary Islands. Our principal interest in this instrument is designing a flexible-testbed for which we can develop a high-order AO system which is suitable for diffraction-limited, visible-light imaging. Additionally, it then becomes a facility which provides a high-order AO corrected beam for further instrument development such as coronography and thus XAO applications. This paper shows our instrument design and the limiting performance estimates. Part of the high-order wavefront sensing is provided by a second interferometric wavefront sensor of novel design to characterise the PSF and resolve quasi-static aberrations to prevent persistent speckle.

Modern extreme adaptive optics (AO) systems achieving diffraction-limited performance open up new possibilities for instrumentation. Especially important for the fields of spectroscopy and interferometry is that it enables the prospect to couple light into single-mode fibers (SMFs). However, due to their small size, efficient coupling is very sensitive to the quality of the fiber alignment, beam drifts and higher-frequency tip-tilt aberrations caused by telescope mechanics and vibrations. These residual aberrations are not always sensed and corrected by the AO system, leading to unacceptable losses. This is particularly severe for the Extremely Large Telescopes, where their huge structure will mean vibrations increase and optimal AO solutions are even more difficult to implement. We have created a focal plane sensor to correct for residual aberrations by surrounding the SMF with six Multi-mode fibers (MMFs). On each of the MMFs sits a printed freeform lens, making up a six-element micro-lens ring to refract the light into these surrounding MMFs and thus minimizing light loss in the gap between the fiber cores. This means when the beam is near diffraction limited and centered almost all light couples to the SMF. When the beam is misaligned, it couples to the surrounding cores, which are read out by a detector and processed by the DARC software driving a tip-tilt mirror. Currently we are aiming to detect and correct only tip-tilt aberrations. However, choosing to surround the central fiber with six sensing locations potentially allows us to investigate higher order correction modes. Here we present the design and performance our prototype system. This has been designed for use with the iLocater fiber injection system at the LBT and can easily be scaled to larger telescopes. We present test results from the KOOL laboratory and initial integration with the iLocater instrument., Comment: AO4ELT6 Conference Proceedings, 7 pages, 4 figures