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Linear, unbranched (1,3;1,4)-ß-glucans (mixed-linkage glucans or MLGs) are commonly found in the cell walls of grasses, but have also been detected in basal land plants, algae, fungi and bacteria. Here we show that two family GT2 glycosyltransferases from the Gram-positive bacterium Sarcina ventriculi are capable of synthesizing MLGs. Immunotransmission electron microscopy demonstrates that MLG is secreted as an exopolysaccharide, where it may play a role in organizing individual cells into packets that are characteristic of Sarcina species. Heterologous expression of these two genes shows that they are capable of producing MLGs in planta, including an MLG that is chemically identical to the MLG secreted from S. ventriculi cells but which has regularly spaced (1,3)-ß-linkages in a structure not reported previously for MLGs. The tandemly arranged, paralogous pair of genes are designated SvBmlgs1 and SvBmlgs2. The data indicate that MLG synthases have evolved different enzymic mechanisms for the incorporation of (1,3)-ß- and (1,4)-ß-glucosyl residues into a single polysaccharide chain. Amino acid variants associated with the evolutionary switch from (1,4)-ß-glucan (cellulose) to MLG synthesis have been identified in the active site regions of the enzymes. The presence of MLG synthesis in bacteria could prove valuable for large-scale production of MLG for medical, food and beverage applications.
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Glicosiltransferasas , beta-Glucanos , Glicosiltransferasas/metabolismo , Glicosiltransferasas/genética , beta-Glucanos/metabolismo , Pared Celular/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Polisacáridos Bacterianos/biosíntesis , Polisacáridos Bacterianos/metabolismoRESUMEN
BACKGROUND: Prior research documented racial and ethnic disparities in health care experiences within the Veterans Health Administration (VA). Little is known about such differences in VA-funded community care programs, through which a growing number of Veterans receive health care. Community care is available to Veterans when care is not available through the VA, nearby, or in a timely manner. OBJECTIVE: To examine differences in Veterans' experiences with VA-funded community care by race and ethnicity and assess changes in these experiences from 2016 to 2021. DESIGN: Observational analyses of Veterans' ratings of community care experiences by self-reported race and ethnicity. We used linear and logistic regressions to estimate racial and ethnic differences in community care experiences, sequentially adjusting for demographic, health, insurance, and socioeconomic factors. PARTICIPANTS: Respondents to the 2016-2021 VA Survey of Healthcare Experiences of Patients-Community Care Survey. MEASURES: Care ratings in nine domains. KEY RESULTS: The sample of 231,869 respondents included 24,306 Black Veterans (mean [SD] age 56.5 [12.9] years, 77.5% male) and 16,490 Hispanic Veterans (mean [SD] age 54.6 [15.9] years, 85.3% male). In adjusted analyses pooled across study years, Black and Hispanic Veterans reported significantly lower ratings than their White and non-Hispanic counterparts in five of nine domains (overall rating of community providers, scheduling a recent appointment, provider communication, non-appointment access, and billing), with adjusted differences ranging from - 0.04 to - 0.13 standard deviations (SDs) of domain scores. Black and Hispanic Veterans reported higher ratings with eligibility determination and scheduling initial appointments than their White and non-Hispanic counterparts, and Black Veterans reported higher ratings of care coordination, with adjusted differences of 0.05 to 0.21 SDs. Care ratings improved from 2016 to 2021, but differences between racial and ethnic groups persisted. CONCLUSIONS: This study identified small but persistent racial and ethnic differences in Veterans' experiences with VA-funded community care, with Black and Hispanic Veterans reporting lower ratings in five domains and, respectively, higher ratings in three and two domains. Interventions to improve Black and Hispanic Veterans' patient experience could advance equity in VA community care.
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BACKGROUND: Although statins are a class I recommendation for prevention of atherosclerotic cardiovascular disease and its complications, their use is suboptimal. Differential underuse may mediate disparities in cardiovascular health for systematically marginalized persons. OBJECTIVE: To estimate disparities in statin use by race-ethnicity-gender and to determine whether these potential disparities are explained by medical appropriateness of therapy and structural factors. DESIGN: Cross-sectional analysis. SETTING: National Health and Nutrition Examination Survey from 2015 to 2020. PARTICIPANTS: Persons eligible for statin therapy based on 2013 and 2018 American College of Cardiology/American Heart Association blood cholesterol guidelines. MEASUREMENTS: The independent variable was race-ethnicity-gender. The outcome of interest was use of a statin. Using the Institute of Medicine framework for examining unequal treatment, we calculated adjusted prevalence ratios (aPRs) to estimate disparities in statin use adjusted for age, disease severity, access to health care, and socioeconomic status relative to non-Hispanic White men. RESULTS: For primary prevention, we identified a lower prevalence of statin use that was not explained by measurable differences in disease severity or structural factors among non-Hispanic Black men (aPR, 0.73 [95% CI, 0.59 to 0.88]) and non-Mexican Hispanic women (aPR, 0.74 [CI, 0.53 to 0.95]). For secondary prevention, we identified a lower prevalence of statin use that was not explained by measurable differences in disease severity or structural factors for non-Hispanic Black men (aPR, 0.81 [CI, 0.64 to 0.97]), other/multiracial men (aPR, 0.58 [CI, 0.20 to 0.97]), Mexican American women (aPR, 0.36 [CI, 0.10 to 0.61]), non-Mexican Hispanic women (aPR, 0.57 [CI, 0.33 to 0.82), non-Hispanic White women (aPR, 0.69 [CI, 0.56 to 0.83]), and non-Hispanic Black women (aPR, 0.75 [CI, 0.57 to 0.92]). LIMITATION: Cross-sectional data; lack of geographic, language, or statin-dose data. CONCLUSION: Statin use disparities for several race-ethnicity-gender groups are not explained by measurable differences in medical appropriateness of therapy, access to health care, and socioeconomic status. These residual disparities may be partially mediated by unobserved processes that contribute to health inequity, including bias, stereotyping, and mistrust. PRIMARY FUNDING SOURCE: National Institutes of Health.
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Aterosclerosis , Enfermedades Cardiovasculares , Disparidades en Atención de Salud , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Adulto , Femenino , Humanos , Masculino , Aterosclerosis/tratamiento farmacológico , Aterosclerosis/epidemiología , Aterosclerosis/etnología , Aterosclerosis/prevención & control , Negro o Afroamericano , Enfermedades Cardiovasculares/tratamiento farmacológico , Estudios Transversales , Etnicidad , Hispánicos o Latinos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Encuestas Nutricionales , Estados Unidos/epidemiología , Blanco , Disparidades en Atención de Salud/etnología , Disparidades en Atención de Salud/estadística & datos numéricosRESUMEN
The effects of homelessness and permanent supportive housing (PSH) on health care utilization have been well documented. Prior research on the association between PSH entry and Medicaid expenditures have indicated that such housing support could result in savings to Medicaid programs; however, whether changes occur in health care use and expenditures after individuals exit PSH is unknown. If efficiency gains from PSH persist after the individual leaves PSH, the savings to payers such as Medicaid may continue even after the costs to provide housing for a PSH recipient have ended. We used linked Medicaid and housing data from Pennsylvania to examine changes in the level and composition of Medicaid expenditures for 580 adult enrollees during the 12 months before and after exit from PSH adjusting for relevant covariates. In adjusted analyses, we estimated that monthly spending declined by $200.32 (95% CI: $323.50, $75.15) in the first quarter post-exit and by $267.63 (95% CI: $406.10, $127.10) in the third quarter. Our findings suggest that PSH may have sustained budgetary benefits to state Medicaid agencies even for beneficiaries exiting the program. However, more research is needed to understand if these reductions in expenditures last beyond 12 months and do not reflect under-use of care that may be important for managing health over the long-term.
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MOTIVATION: Bioinformatics software tools operate largely through the use of specialized genomics file formats. Often these formats lack formal specification, making it difficult or impossible for the creators of these tools to robustly test them for correct handling of input and output. This causes problems in interoperability between different tools that, at best, wastes time and frustrates users. At worst, interoperability issues could lead to undetected errors in scientific results. RESULTS: We developed a new verification system, Acidbio, which tests for correct behavior in bioinformatics software packages. We crafted tests to unify correct behavior when tools encounter various edge cases-potentially unexpected inputs that exemplify the limits of the format. To analyze the performance of existing software, we tested the input validation of 80 Bioconda packages that parsed the Browser Extensible Data (BED) format. We also used a fuzzing approach to automatically perform additional testing. Of 80 software packages examined, 75 achieved less than 70% correctness on our test suite. We categorized multiple root causes for the poor performance of different types of software. Fuzzing detected other errors that the manually designed test suite could not. We also created a badge system that developers can use to indicate more precisely which BED variants their software accepts and to advertise the software's performance on the test suite. AVAILABILITY AND IMPLEMENTATION: Acidbio is available at https://github.com/hoffmangroup/acidbio. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.
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Genómica , Programas Informáticos , Genómica/métodosRESUMEN
BACKGROUND: Maternal prenatal exposure to air pollution has been associated with adverse birth outcomes. However, previous studies focused on a priori time intervals such as trimesters reported inconsistent associations. OBJECTIVES: We investigated time-varying vulnerability of birth weight to fine particulate matter (PM2.5) and nitrogen dioxide (NO2) using flexible time intervals. METHODS: We analyzed 1,300 live, full-term births from Maternal-Infant Research on Environmental Chemicals, a Canadian prospective pregnancy cohort spanning 10 cities (2008-2011). Daily PM2.5 and NO2 concentrations were estimated from ground-level monitoring, satellite models, and land-use regression, and assigned to participants from pre-pregnancy through delivery. We developed a flexible two-stage modeling method-using a Bayesian Metropolis-Hastings algorithm and empirical density threshold-to identify time-dependent vulnerability to air pollution without specifying exposure periods a priori. This approach identified critical windows with varying lengths (2-363 days) and critical windows that fell within, or straddled, predetermined time periods (i.e., trimesters). We adjusted the models for detailed infant and maternal covariates. RESULTS: Critical windows associated with reduced birth weight were identified during mid- to late-pregnancy for both PM2.5 and NO2: -6 g (95% credible interval: -11, -1 g) and -5 g (-10, -0.1 g) per µg/m3 PM2.5 during gestational days 91-139 and 249-272, respectively; and -3 g (-5, -1 g) per ppb NO2 during days 55-145. DISCUSSION: We used a novel, flexible selection method to identify critical windows when maternal exposures to air pollution were associated with decrements in birth weight. Our results suggest that air pollution impacts on fetal development may not be adequately captured by trimester-based analyses.
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Contaminantes Atmosféricos , Contaminación del Aire , Peso al Nacer , Exposición Materna , Contaminantes Atmosféricos/análisis , Contaminación del Aire/análisis , Contaminación del Aire/estadística & datos numéricos , Teorema de Bayes , Canadá/epidemiología , Femenino , Humanos , Exposición Materna/estadística & datos numéricos , Material Particulado/análisis , Embarazo , Estudios ProspectivosRESUMEN
Importance: Medicaid is the largest health insurance program by enrollment in the US and has an important role in financing care for eligible low-income adults, children, pregnant persons, older adults, people with disabilities, and people from racial and ethnic minority groups. Medicaid has evolved with policy reform and expansion under the Affordable Care Act and is at a crossroads in balancing its role in addressing health disparities and health inequities against fiscal and political pressures to limit spending. Objective: To describe Medicaid eligibility, enrollment, and spending and to examine areas of Medicaid policy, including managed care, payment, and delivery system reforms; Medicaid expansion; racial and ethnic health disparities; and the potential to achieve health equity. Evidence Review: Analyses of publicly available data reported from 2010 to 2022 on Medicaid enrollment and program expenditures were performed to describe the structure and financing of Medicaid and characteristics of Medicaid enrollees. A search of PubMed for peer-reviewed literature and online reports from nonprofit and government organizations was conducted between August 1, 2021, and February 1, 2022, to review evidence on Medicaid managed care, delivery system reforms, expansion, and health disparities. Peer-reviewed articles and reports published between January 2003 and February 2022 were included. Findings: Medicaid covered approximately 80.6 million people (mean per month) in 2022 (24.2% of the US population) and accounted for an estimated $671.2 billion in health spending in 2020, representing 16.3% of US health spending. Medicaid accounted for an estimated 27.2% of total state spending and 7.6% of total federal expenditures in 2021. States enrolled 69.5% of Medicaid beneficiaries in managed care plans in 2019 and adopted 139 delivery system reforms from 2003 to 2019. The 38 states (and Washington, DC) that expanded Medicaid under the Affordable Care Act experienced gains in coverage, increased federal revenues, and improvements in health care access and some health outcomes. Approximately 56.4% of Medicaid beneficiaries were from racial and ethnic minority groups in 2019, and disparities in access, quality, and outcomes are common among these groups within Medicaid. Expanding Medicaid, addressing disparities within Medicaid, and having an explicit focus on equity in managed care and delivery system reforms may represent opportunities for Medicaid to advance health equity. Conclusions and Relevance: Medicaid insures a substantial portion of the US population, accounts for a significant amount of total health spending and state expenditures, and has evolved with delivery system reforms, increased managed care enrollment, and state expansions. Additional Medicaid policy reforms are needed to reduce health disparities by race and ethnicity and to help achieve equity in access, quality, and outcomes.
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Reforma de la Atención de Salud , Equidad en Salud , Medicaid , Anciano , Niño , Etnicidad , Femenino , Reforma de la Atención de Salud/economía , Equidad en Salud/normas , Humanos , Cobertura del Seguro/economía , Medicaid/economía , Medicaid/organización & administración , Medicaid/normas , Grupos Minoritarios/estadística & datos numéricos , Patient Protection and Affordable Care Act/economía , Embarazo , Estados Unidos/epidemiologíaRESUMEN
Mixed-linkage (1,3;1,4)-ß-glucan (MLG), an abundant cell wall polysaccharide in the Poaceae, has been detected in ascomycetes, algae, and seedless vascular plants, but not in eudicots. Although MLG has not been reported in bryophytes, a predicted glycosyltransferase from the moss Physcomitrella patens (Pp3c12_24670) is similar to a bona fide ascomycete MLG synthase. We tested whether Pp3c12_24670 encodes an MLG synthase by expressing it in wild tobacco (Nicotiana benthamiana) and testing for release of diagnostic oligosaccharides from the cell walls by either lichenase or (1,4)-ß-glucan endohydrolase. Lichenase, an MLG-specific endohydrolase, showed no activity against cell walls from transformed N. benthamiana, but (1,4)-ß-glucan endohydrolase released oligosaccharides that were distinct from oligosaccharides released from MLG by this enzyme. Further analysis revealed that these oligosaccharides were derived from a novel unbranched, unsubstituted arabinoglucan (AGlc) polysaccharide. We identified sequences similar to the P. patens AGlc synthase from algae, bryophytes, lycophytes, and monilophytes, raising the possibility that other early divergent plants synthesize AGlc. Similarity of P. patens AGlc synthase to MLG synthases from ascomycetes, but not those from Poaceae, suggests that AGlc and MLG have a common evolutionary history that includes loss in seed plants, followed by a more recent independent origin of MLG within the monocots.
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Bryopsida/metabolismo , Pared Celular/metabolismo , Glucanos/metabolismo , Glicosiltransferasas/metabolismoRESUMEN
BACKGROUND: There is growing interest in financing housing and supportive services for homeless individuals through Medicaid. Permanent Supportive Housing (PSH), which integrates non-time-limited housing with supportive services for people who are disabled and chronically homeless, has seen rapid growth in the last decade, but clear evidence on the long-term impacts of PSH, needed to guide state efforts to finance some PSH services through Medicaid, is lacking. OBJECTIVE: Assess changes in Medicaid expenditures and utilization associated with receiving PSH. DESIGN: Cohort study using a difference-in-differences approach. PARTICIPANTS: A total of 1226 PA Medicaid enrollees who entered PSH 2011-2016 and remained in PSH for 180 days or more, and a matched comparison cohort of 970 enrollees experiencing housing instability who did not receive PSH. MAIN MEASURES: Medicaid spending in aggregate, and on behavioral and physical health services; emergency department (ED) visits and inpatient hospital stays. KEY RESULTS: Three years after PSH entry, spending decreased by an average of $145/month in the PSH cohort relative to changes in the comparison cohort (p = 0.046), with the greatest relative spending reductions occurring for residential behavioral health ($64, p < 0.001) and inpatient non-behavioral health services ($89, p = 0.001). We also found relative reductions in ED use (4.7 visits/100 person-months, p = 0.010) and inpatient hospital stays (1.6 visits/100 person-months, p < 0.001). CONCLUSIONS: These results can inform emerging state efforts to finance PSH services through Medicaid. Additional state expenditures to expand financing for PSH services could be partially offset by reductions in Medicaid spending, in part by facilitating a shift in treatment to outpatient from acute care settings.
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Personas con Mala Vivienda , Medicaid , Adulto , Estudios de Cohortes , Servicio de Urgencia en Hospital , Vivienda , Humanos , Estados Unidos/epidemiologíaRESUMEN
Summary: Segway performs semi-automated genome annotation, discovering joint patterns across multiple genomic signal datasets. We discuss a major new version of Segway and highlight its ability to model data with substantially greater accuracy. Major enhancements in Segway 2.0 include the ability to model data with a mixture of Gaussians, enabling capture of arbitrarily complex signal distributions, and minibatch training, leading to better learned parameters. Availability and implementation: Segway and its source code are freely available for download at http://segway.hoffmanlab.org. We have made available scripts (https://doi.org/10.5281/zenodo.802939) and datasets (https://doi.org/10.5281/zenodo.802906) for this paper's analysis. Contact: michael.hoffman@utoronto.ca. Supplementary information: Supplementary data are available at Bioinformatics online.
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Genómica/métodos , Anotación de Secuencia Molecular/métodos , Análisis de Secuencia de ADN/métodos , Programas Informáticos , Eucariontes/genéticaRESUMEN
BACKGROUND: Less than 25% of stroke patients arrive to an emergency department within the 3-hour treatment window. OBJECTIVE: We evaluated the cost-effectiveness of a stroke preparedness behavioral intervention study (Stroke Warning Information and Faster Treatment [SWIFT]), a stroke intervention demonstrating capacity to decrease race-ethnic disparities in ED arrival times. METHODS: Using the literature and SWIFT outcomes for 2 interventions, enhanced educational (EE) materials, and interactive intervention (II), we assess the cost-effectiveness of SWIFT in 2 ways: (1) Markov model, and (2) cost-to-outcome ratio. The Markov model primary outcome was the cost per quality-adjusted life-year (QALY) gained using the cost-effectiveness threshold of $100 000/QALY. The primary cost-to-outcome endpoint was cost per additional patient with ED arrival <3 hours, stroke knowledge, and preparedness capacity. We assessed the ICER of II and EE versus standard care (SC) from a health sector and societal perspective using 2015 USD, a time horizon of 5 years, and a discount rate of 3%. RESULTS: The cost-effectiveness of the II and EE programs was, respectively, $227.35 and $74.63 per additional arrival <3 hours, $440.72 and $334.09 per additional person with stroke knowledge proficiency, and $655.70 and $811.77 per additional person with preparedness capacity. Using a societal perspective, the ICER for EE versus SC was $84 643 per QALY gained and the ICER for II versus EE was $59 058 per QALY gained. Incorporating fixed costs, EE and II would need to administered to 507 and 1693 or more patients, respectively, to achieve an ICER of $100 000/QALY. CONCLUSION: II was a cost-effective strategy compared with both EE and SC. Nevertheless, high initial fixed costs associated with II may limit its cost-effectiveness in settings with smaller patient populations.
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Educación en Salud/organización & administración , Accidente Cerebrovascular/tratamiento farmacológico , Accidente Cerebrovascular/epidemiología , Activador de Tejido Plasminógeno/administración & dosificación , Anciano , Análisis Costo-Beneficio , Femenino , Educación en Salud/economía , Servicios de Salud/economía , Servicios de Salud/estadística & datos numéricos , Humanos , Masculino , Cadenas de Markov , Persona de Mediana Edad , Modelos Económicos , Años de Vida Ajustados por Calidad de Vida , Factores Socioeconómicos , Accidente Cerebrovascular/economía , Factores de Tiempo , Activador de Tejido Plasminógeno/uso terapéuticoRESUMEN
Fossil dinosaur embryos are surprisingly rare, being almost entirely restricted to Upper Cretaceous strata that record the late stages of non-avian dinosaur evolution. Notable exceptions are the oldest known embryos from the Early Jurassic South African sauropodomorph Massospondylus and Late Jurassic embryos of a theropod from Portugal. The fact that dinosaur embryos are rare and typically enclosed in eggshells limits their availability for tissue and cellular level investigations of development. Consequently, little is known about growth patterns in dinosaur embryos, even though post-hatching ontogeny has been studied in several taxa. Here we report the discovery of an embryonic dinosaur bone bed from the Lower Jurassic of China, the oldest such occurrence in the fossil record. The embryos are similar in geological age to those of Massospondylus and are also assignable to a sauropodomorph dinosaur, probably Lufengosaurus. The preservation of numerous disarticulated skeletal elements and eggshells in this monotaxic bone bed, representing different stages of incubation and therefore derived from different nests, provides opportunities for new investigations of dinosaur embryology in a clade noted for gigantism. For example, comparisons among embryonic femora of different sizes and developmental stages reveal a consistently rapid rate of growth throughout development, possibly indicating that short incubation times were characteristic of sauropodomorphs. In addition, asymmetric radial growth of the femoral shaft and rapid expansion of the fourth trochanter suggest that embryonic muscle activation played an important role in the pre-hatching ontogeny of these dinosaurs. This discovery also provides the oldest evidence of in situ preservation of complex organic remains in a terrestrial vertebrate.
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Dinosaurios/anatomía & histología , Dinosaurios/embriología , Fósiles , Animales , China , Fémur/anatomía & histología , Fémur/embriología , Espectroscopía Infrarroja por Transformada de Fourier , SincrotronesRESUMEN
Apes and Old World monkeys are prominent components of modern African and Asian ecosystems, yet the earliest phases of their evolutionary history have remained largely undocumented. The absence of crown catarrhine fossils older than â¼20 million years (Myr) has stood in stark contrast to molecular divergence estimates of â¼25-30 Myr for the split between Cercopithecoidea (Old World monkeys) and Hominoidea (apes), implying long ghost lineages for both clades. Here we describe the oldest known fossil 'ape', represented by a partial mandible preserving dental features that place it with 'nyanzapithecine' stem hominoids. Additionally, we report the oldest stem member of the Old World monkey clade, represented by a lower third molar. Both specimens were recovered from a precisely dated 25.2-Myr-old stratum in the Rukwa Rift, a segment of the western branch of the East African Rift in Tanzania. These finds extend the fossil record of apes and Old World monkeys well into the Oligocene epoch of Africa, suggesting a possible link between diversification of crown catarrhines and changes in the African landscape brought about by previously unrecognized tectonic activity in the East African rift system.
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Cercopithecidae/clasificación , Fósiles , Hominidae/clasificación , Filogenia , Animales , Cercopithecidae/anatomía & histología , Historia Antigua , Hominidae/anatomía & histología , Mandíbula/anatomía & histología , Tanzanía , Diente/anatomía & histologíaRESUMEN
Background: When risk adjustment is inadequate and incentives are weak, pay-for-performance programs, such as the Value-Based Payment Modifier (Value Modifier [VM]) implemented by the Centers for Medicare & Medicaid Services, may contribute to health care disparities without improving performance on average. Objective: To estimate the association between VM exposure and performance on quality and spending measures and to assess the effects of adjusting for additional patient characteristics on performance differences between practices serving higher-risk and those serving lower-risk patients. Design: Exploiting the phase-in of the VM on the basis of practice size, regression discontinuity analysis and 2014 Medicare claims were used to estimate differences in practice performance associated with exposure of practices with 100 or more clinicians to full VM incentives (bonuses and penalties) and exposure of practices with 10 or more clinicians to partial incentives (bonuses only). Analyses were repeated with 2015 claims to estimate performance differences associated with a second year of exposure above the threshold of 100 or more clinicians. Performance differences were assessed between practices serving higher- and those serving lower-risk patients after standard Medicare adjustments versus adjustment for additional patient characteristics. Setting: Fee-for-service Medicare. Patients: Random 20% sample of beneficiaries. Measurements: Hospitalization for ambulatory care-sensitive conditions, all-cause 30-day readmissions, Medicare spending, and mortality. Results: No statistically significant discontinuities were found at the threshold of 10 or more or 100 or more clinicians in the relationship between practice size and performance on quality or spending measures in either year. Adjustment for additional patient characteristics narrowed performance differences by 9.2% to 67.9% between practices in the highest and those in the lowest quartile of Medicaid patients and Hierarchical Condition Category scores. Limitation: Observational design and administrative data. Conclusion: The VM was not associated with differences in performance on program measures. Performance differences between practices serving higher- and those serving lower-risk patients were affected considerably by additional adjustments, suggesting a potential for Medicare's pay-for-performance programs to exacerbate health care disparities. Primary Funding Source: The Laura and John Arnold Foundation and National Institute on Aging.
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Planes de Aranceles por Servicios/economía , Disparidades en Atención de Salud/economía , Medicare/economía , Calidad de la Atención de Salud/economía , Reembolso de Incentivo/economía , Anciano , Centers for Medicare and Medicaid Services, U.S. , Femenino , Gastos en Salud , Hospitalización/economía , Humanos , Masculino , Readmisión del Paciente/economía , Ajuste de Riesgo , Estados UnidosRESUMEN
Topological entropy measures the number of distinguishable orbits in a dynamical system, thereby quantifying the complexity of chaotic dynamics. One approach to computing topological entropy in a two-dimensional space is to analyze the collective motion of an ensemble of system trajectories taking into account how trajectories "braid" around one another. In this spirit, we introduce the Ensemble-based Topological Entropy Calculation, or E-tec, a method to derive a lower-bound on topological entropy of two-dimensional systems by considering the evolution of a "rubber band" (piece-wise linear curve) wrapped around the data points and evolving with their trajectories. The topological entropy is bounded below by the exponential growth rate of this band. We use tools from computational geometry to track the evolution of the rubber band as data points strike and deform it. Because we maintain information about the configuration of trajectories with respect to one another, updating the band configuration is performed locally, which allows E-tec to be more computationally efficient than some competing methods. In this work, we validate and illustrate many features of E-tec on a chaotic lid-driven cavity flow. In particular, we demonstrate convergence of E-tec's approximation with respect to both the number of trajectories (ensemble size) and the duration of trajectories in time.
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BACKGROUND: Pesticides exposures are aspects of the human exposome that have not been sufficiently studied for their contribution to risk for preterm birth. We investigated risks of spontaneous preterm birth from potential residential exposures to 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. METHODS: The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. After exclusions, the analytic study base included 197,461 term control births and 27,913 preterm case births. Preterm cases were more narrowly defined as 20-23 weeks (n = 515), 24-27 weeks (n = 1,792), 28-31 weeks (n = 3,098), or 32-36 weeks (n = 22,508). RESULTS: The frequency of any (versus none) pesticide exposure was uniformly lower in each preterm case group relative to the frequency in term controls, irrespective of gestational month of exposure. All odds ratios were below 1.0 for these any versus no exposure comparisons. The majority of odds ratios were below 1.0, many of them statistically precise, for preterm birth and exposures to specific chemical groups or chemicals. CONCLUSIONS: This study showed a general lack of increased risk of preterm birth associated with a range of agriculture pesticide exposures near women's residences.
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Agricultura , Exposición a Riesgos Ambientales/estadística & datos numéricos , Exposición Materna/estadística & datos numéricos , Plaguicidas , Nacimiento Prematuro/epidemiología , Adulto , California/epidemiología , Estudios de Casos y Controles , Femenino , Edad Gestacional , Humanos , Recién Nacido , Masculino , Oportunidad Relativa , Embarazo , Adulto JovenRESUMEN
Data from traditional public health surveillance systems can have some limitations, e.g., timeliness, geographic level, and amount of data accessible. Electronic health records (EHRs) could present an opportunity to supplement current sources of routinely collected surveillance data. The National Environmental Public Health Tracking Program (Tracking Program) sought to explore the use of EHRs for advancing environmental public health surveillance practices. The Tracking Program funded four state/local health departments to obtain and pilot the use of EHR data to address several issues including the challenges and technical requirements for accessing EHR data, and the core data elements required to integrate EHR data within their departments' Tracking Programs. The results of these pilot projects highlighted the potential of EHR data for public health surveillance of rare diseases that may lack comprehensive registries, and surveillance of prevalent health conditions or risk factors for health outcomes at a finer geographic level. EHRs therefore, may have potential to supplement traditional sources of public health surveillance data.
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Registros Electrónicos de Salud , Salud Pública/métodos , Enfermedades Raras/epidemiología , Adulto , Anciano , Esclerosis Amiotrófica Lateral/epidemiología , California , Recolección de Datos , Hemoglobina Glucada/análisis , Humanos , Massachusetts , Persona de Mediana Edad , Ciudad de Nueva York , Enfermedades Raras/diagnóstico , Sistema de Registros , Factores de Riesgo , Adulto JovenRESUMEN
We investigated risks of preeclampsia phenotypes from potential residential pesticide exposures, including 543 individual chemicals and 69 physicochemical groupings that were applied in the San Joaquin Valley of California during the study period, 1998-2011. The study population was derived from birth certificate data linked with Office of Statewide Health Planning and Development maternal and infant hospital discharge data. The following numbers of women with preeclampsia phenotypes were identified: 1045 with superimposed (pre-existing hypertension with preeclampsia) preeclampsia (265 with gestational weeks 20-31 and 780 with gestational weeks 32-36); 3471 with severe preeclampsia (824 with gestational weeks 20-31 and 2647 with gestational weeks 32-36); and 2780 with mild preeclampsia (207 with gestational weeks 20-31 and 2573 with gestational weeks 32-36). The reference population for these groups was 197,461 women who did not have diabetes (gestational or pre-existing), did not have any hypertensive disorder, and who delivered at 37 weeks or later. The frequency of any exposure was lower or about the same in each preeclampsia case group (further delineated by gestational age), and month time period, relative to the frequency in reference population controls. Nearly all odds ratios were below 1.0 for these any vs no exposure comparisons. This study showed a general lack of increased risks between a range of agriculture pesticide exposures near women's residences and various preeclampsia phenotypes.