3,221 research outputs found

    Constraining recent lead pollution sources in the North Pacific using ice core stable lead isotopes

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    Trends and sources of lead (Pb) aerosol pollution in the North Pacific rim of North America from 1850 to 2001 are investigated using a high-resolution (subannual to annual) ice core record recovered from Eclipse Icefield (3017 masl; St. Elias Mountains, Canada). Beginning in the early 1940s, increasing Pb concentration at Eclipse Icefield occurs coevally with anthropogenic Pb deposition in central Greenland, suggesting that North American Pb pollution may have been in part or wholly responsible in both regions. Isotopic ratios (208Pb/207Pb and 206Pb/207Pb) from 1970 to 2001 confirm that a portion of the Pb deposited at Eclipse Icefield is anthropogenic, and that it represents a variable mixture of East Asian (Chinese and Japanese) emissions transported eastward across the Pacific Ocean and a North American component resulting from transient meridional atmospheric flow. Based on comparison with source material Pb isotope ratios, Chinese and North American coal combustion have likely been the primary sources of Eclipse Icefield Pb over the 1970–2001 time period. The Eclipse Icefield Pb isotope composition also implies that the North Pacific mid-troposphere is not directly impacted by transpolar atmospheric flow from Europe. Annually averaged Pb concentrations in the Eclipse Icefield ice core record show no long-term trend during 1970–2001; however, increasing 208Pb/207Pb and decreasing 206Pb/207Pb ratios reflect the progressive East Asian industrialization and increase in Asian pollutant outflow. The post-1970 decrease in North American Pb emissions is likely necessary to explain the Eclipse Icefield Pb concentration time series. When compared with low (lichen) and high (Mt. Logan ice core) elevation Pb data, the Eclipse ice core record suggests a gradual increase in pollutant deposition and stronger trans-Pacific Asian contribution with rising elevation in the mountains of the North Pacific rim

    Three Years In--Changing Plan Features in the U.S. Health Insurance Marketplace

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    Background: A central objective of recent U.S. healthcare policy reform, most notably the Affordable Care Act\u27s (ACA) Health Insurance Marketplace, has been to increase access to stable, affordable health insurance. However, changing market dynamics (rising premiums, changes in issuer participation and plan availability) raise significant concerns about the marketplaces\u27 ability to provide a stable source of healthcare for Americans that rely on them. By looking at the effect of instability on changes in the consumer choice set, we can analyze potential incentives to switch plans among price-sensitive enrollees, which can then be used to inform policy going forward. Methods: Data on health plan features for non-tobacco users in 2512 counties in 34 states participating in federally-facilitated exchanges from 2014 to 2016 was obtained from the Centers for Medicaid & Medicare Services. We examined how changes in individual plan features, including premiums, deductibles, issuers, and plan types, impact consumers who had purchased the lowest-cost silver or bronze plan in their county the previous year. We calculated the cost of staying in the same plan versus switching to another plan the following year, and analyzed how costs vary across geographic regions. Results: In most counties in 2015 and 2016 (53.7 and 68.2%, respectively), the lowest-cost silver plan from the previous year was still available, but was no longer the cheapest plan. In these counties, consumers who switched to the new lowest-cost plan would pay less in monthly premiums on average, by 51.48and51.48 and 55.01, respectively, compared to staying in the same plan. Despite potential premium savings from switching, however, the majority would still pay higher average premiums compared to the previous year, and most would face higher deductibles and an increased probability of having to change provider networks. Conclusion: While the ACA has shown promise in expanding healthcare access, continued changes in the availability and affordability of health plans are likely to result in churning and switching among enrollees, which may have negative ramifications for their health going forward. Future healthcare policy reform should aim to stabilize marketplace dynamics in order to encourage greater care continuity and limit churning

    Three years in – changing plan features in the U.S. health insurance marketplace

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    Abstract Background A central objective of recent U.S. healthcare policy reform, most notably the Affordable Care Act’s (ACA) Health Insurance Marketplace, has been to increase access to stable, affordable health insurance. However, changing market dynamics (rising premiums, changes in issuer participation and plan availability) raise significant concerns about the marketplaces’ ability to provide a stable source of healthcare for Americans that rely on them. By looking at the effect of instability on changes in the consumer choice set, we can analyze potential incentives to switch plans among price-sensitive enrollees, which can then be used to inform policy going forward. Methods Data on health plan features for non-tobacco users in 2512 counties in 34 states participating in federally-facilitated exchanges from 2014 to 2016 was obtained from the Centers for Medicaid & Medicare Services. We examined how changes in individual plan features, including premiums, deductibles, issuers, and plan types, impact consumers who had purchased the lowest-cost silver or bronze plan in their county the previous year. We calculated the cost of staying in the same plan versus switching to another plan the following year, and analyzed how costs vary across geographic regions. Results In most counties in 2015 and 2016 (53.7 and 68.2%, respectively), the lowest-cost silver plan from the previous year was still available, but was no longer the cheapest plan. In these counties, consumers who switched to the new lowest-cost plan would pay less in monthly premiums on average, by 51.48and51.48 and 55.01, respectively, compared to staying in the same plan. Despite potential premium savings from switching, however, the majority would still pay higher average premiums compared to the previous year, and most would face higher deductibles and an increased probability of having to change provider networks. Conclusion While the ACA has shown promise in expanding healthcare access, continued changes in the availability and affordability of health plans are likely to result in churning and switching among enrollees, which may have negative ramifications for their health going forward. Future healthcare policy reform should aim to stabilize marketplace dynamics in order to encourage greater care continuity and limit churning.https://deepblue.lib.umich.edu/bitstream/2027.42/144501/1/12913_2018_Article_3198.pd

    Patient-Centered Medical Homes in Community Oncology Practices: Changes in Spending and Care Quality Associated With the COME HOME Experience

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    PURPOSE: We examined whether the Community Oncology Medical Home (COME HOME) program, a medical home program implemented in seven community oncology practices, was associated with changes in spending and care quality. PATIENTS AND METHODS: We compared outcomes from elderly fee-for-service Medicare beneficiaries diagnosed between 2011 and 2015 with breast, lung, colorectal, thyroid, or pancreatic cancer, lymphoma, or melanoma and served by COME HOME practices before and after program implementation versus similar beneficiaries served by other geographically proximate oncologists. Difference-in-differences analysis compared changes in outcomes for COME HOME patients versus concurrent controls. Propensity score matching and regression methods were adjusted for clinical and sociodemographic differences. Our primary outcome was 6-month medical spending per beneficiary. Secondary outcomes included 6-month out-of-pocket spending, inpatient and ambulatory care–sensitive hospitalizations, readmissions, length of stay, and emergency department and evaluation and management visits. RESULTS: Before COME HOME, 6-month medical spending was 2,975higherforthestudygroupcomparedwithcontrols(952,975 higher for the study group compared with controls (95% CI, 1,635 to 4,315;P3˘c.001)andincreasingatasimilarrate.Afterintervention,thisdifferencewasreducedto4,315; P \u3c .001) and increasing at a similar rate. After intervention, this difference was reduced to 318 (95% CI, −1,105to1,105 to 1,741; P = .661), a significant change of −2,657(952,657 (95% CI, −4,631 to −683;P=.008)or8.1683; P = .008) or 8.1% savings relative to 6-month average spending (32,866). COME HOME was also associated with significantly reduced (10.2 %) emergency department visits per 1,000 patients per 6-month period (P = .024). There were no statistically significant differences in other outcomes. CONCLUSION: COME HOME was associated with reduced Medicare spending and improved emergency department use. The patient-centered medical home model holds promise for oncology practices, but improvements were not uniform

    Lost and Found: A New Position and Infrared Counterpart for the X-ray Binary Scutum X-1

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    Using archival X-ray data, we find that the catalog location of the X-ray binary Scutum X-1 (Sct X-1) is incorrect, and that the correct location is that of the X-ray source AX J183528-0737, which is 15' to the west. Our identification is made on the basis of the 112-s pulse period for this object detected in an XMM-Newton observation, as well as spatial coincidence between AX J183528-0737 and previous X-ray observations. Based on the XMM-Newton data and archival RXTE data, we confirm secular spin-down over 17 years with period derivative Pdot~3.9e-9 s/s, but do not detect a previously reported X-ray iron fluorescence line. We identify a bright (Ks=6.55), red (J-Ks=5.51), optical and infrared counterpart to AX J183528-0737 from 2MASS, a number of mid-IR surveys, and deep optical observations, which we use to constrain the extinction to and distance of Sct X-1. From these data, as well as limited near-IR spectroscopy, we conclude that Sct X-1 is most likely a binary system comprised of a late-type giant or supergiant and a neutron star.Comment: 10 pages, 9 figures. Revised following referee's comments. Accepted to Ap

    Constraining the Proper Motions of Two Magnetars

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    We attempt to measure the proper motions of two magnetars - the soft gamma-ray repeater SGR 1900+14 and the anomalous X-ray pulsar 1E 2259+586 - using two epochs of Chandra observations separated by ~5 yr. We perform extensive tests using these data, archival data, and simulations to verify the accuracy of our measurements and understand their limitations. We find 90% upper limits on the proper motions of 54 mas/yr (SGR 1900+14) and 65 mas/yr (1E 2259+586), with the limits largely determined by the accuracy with which we could register the two epochs of data and by the inherent uncertainties on two-point proper motions. We translate the proper motions limits into limits on the transverse velocity using distances, and find v_perp < 1300 km/s (SGR 1900+14, for a distance of 5 kpc) and v_perp < 930 km/s (1E 2259+586, for a distance of 3 kpc) at 90% confidence; the range of possible distances for these objects makes a wide range of velocities possible, but it seems that the magnetars do not have uniformly high space velocities of > 3000 km/s. Unfortunately, our proper motions also cannot significantly constrain the previously proposed origins of these objects in nearby supernova remnants or star clusters, limited as much by our ignorance of ages as by our proper motions.Comment: 12 pages, 9 figures. Accepted for publication in A

    Q-TWiST analysis of lapatinib combined with capecitabine for the treatment of metastatic breast cancer

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    The addition of lapatinib (Tykerb/Tyverb) to capecitabine (Xeloda) delays disease progression more effectively than capecitabine monotherapy in women with previously treated HER2+ metastatic breast cancer (MBC). The quality-adjusted time without symptoms of disease or toxicity of treatment (Q-TWiST) method was used to compare treatments. The area under survival curves was partitioned into health states: toxicity (TOX), time without symptoms of disease progression or toxicity (TWiST), and relapse period until death or end of follow-up (REL). Average times spent in each state, weighted by utility, were derived and comparisons of Q-TWiST between groups performed with varying combinations of the utility weights. Utility weights of 0.5 for both TOX and REL, that is, counting 2 days of TOX or REL as 1 day of TWiST, resulted in a 7-week difference in quality-adjusted survival favouring combination therapy (P=0.0013). The Q-TWiST difference is clinically meaningful and was statistically significant across an entire matrix of possible utility weights. Results were robust in sensitivity analyses. An analysis with utilities based on EQ-5D scores was consistent with the above findings. Combination therapy of lapatinib with capecitabine resulted in greater quality-adjusted survival than capecitabine monotherapy in trastuzumab-refractory MBC patients

    Efficacy of a Single Image-Guided Corticosteroid Injection for Glenohumeral Arthritis

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    Background There is limited data available on the efficacy of cortisone injection for glenohumeral osteoarthritis (GHOA). The amount and longevity of pain relief provided by a single cortisone injection is unclear. Additionally, it remains uncertain how the severity of radiographic GHOA and patient reported function and pain levels impact the efficacy of injection. Therefore, we sought to describe relief provided by a single, image guided glenohumeral injection for patients with GHOA. Additionally, we hypothesized that patients with more severe radiographic GHOA and poorer baseline shoulder function would require earlier secondary intervention. Methods Patients with symptomatic GHOA who elected to receive a corticosteroid injection for pain relief were prospectively enrolled. A phone interview was conducted to record baseline OSS and VAS scores prior to the injection, as well as at months 1, 2, 3, 4, 6, 9, and 12. Endpoints were designated when patients required a second injection, progressed to surgery, or reached month 12. Patients were grouped by their respective baseline OSS (mild, moderate/severe) and Samilson-Prieto radiographic classification (mild, moderate, severe) for analysis. Results Thirty shoulders (29 patients) were analyzed. 52% of patients were male. The average age of 66.1 years. No significant difference was seen in overall survival (defined as no additional intervention) between groups based on either OSS or Samilson-Prieto grades. Additionally, OSS and VAS scores at each follow-up were compared to baseline. For the entire cohort, a clinically significant difference was seen between baseline and months 1-4 for OSS and between baseline and months 1-4, 6,9, and 12 for VAS. Discussion This study aimed to determine the efficacy of corticosteroid injections for GHOA. There were no differences in the need for secondary interventions in this population based on severity of either the OSS or the Samilson-Prieto radiographic classification. However, patients with more severe shoulder dysfunction based on OSS did experience a statistically significant greater symptomatic relief compared with patients with milder dysfunction. Additionally, following a single injection, patients in this cohort experienced statistically and clinically relevant improvements in shoulder function and pain up to 4 months post-injection

    The cost of changing physical activity behaviour: Evidence from a "physical activity pathway" in the primary care setting

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    Copyright @ 2011 Boehler et al.BACKGROUND: The ‘Physical Activity Care Pathway’ (a Pilot for the ‘Let’s Get Moving’ policy) is a systematic approach to integrating physical activity promotion into the primary care setting. It combines several methods reported to support behavioural change, including brief interventions, motivational interviewing, goal setting, providing written resources, and follow-up support. This paper compares costs falling on the UK National Health Service (NHS) of implementing the care pathway using two different recruitment strategies and provides initial insights into the cost of changing physical activity behaviour. METHODS: A combination of a time driven variant of activity based costing, audit data through EMIS and a survey of practice managers provided patient-level cost data for 411 screened individuals. Self reported physical activity data of 70 people completing the care pathway at three month was compared with baseline using a regression based ‘difference in differences’ approach. Deterministic and probabilistic sensitivity analyses in combination with hypothesis testing were used to judge how robust findings are to key assumptions and to assess the uncertainty around estimates of the cost of changing physical activity behaviour. RESULTS: It cost £53 (SD 7.8) per patient completing the PACP in opportunistic centres and £191 (SD 39) at disease register sites. The completer rate was higher in disease register centres (27.3% vs. 16.2%) and the difference in differences in time spent on physical activity was 81.32 (SE 17.16) minutes/week in patients completing the PACP; so that the incremental cost of converting one sedentary adult to an ‘active state’ of 150 minutes of moderate intensity physical activity per week amounts to £ 886.50 in disease register practices, compared to opportunistic screening. CONCLUSIONS: Disease register screening is more costly than opportunistic patient recruitment. However, additional costs come with a higher completion rate and better outcomes in terms of behavioural change in patients completing the care pathway. Further research is needed to rigorously evaluate intervention efficiency and to assess the link between behavioural change and changes in quality adjusted life years (QALYs).This article is available through the Brunel Open Access Publishing Fund
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