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State legislatures are tasked with drawing state and federal districts and administering election law, among many other responsibilities. Yet state legislatures are themselves gerrymandered. This book examines how, why, and with what consequences, drawing on an original dataset of ninety-five state legislative maps from before and after 2011 redistricting. Identifying the institutional, political, and geographic determinants of gerrymandering, the authors find that Republican gerrymandering increased dramatically after the 2011 redistricting and bias was most extreme in states with racial segregation where Republicans drew the maps. This bias has had long-term consequences. For instance, states with the most extreme Republican gerrymandering were more likely to pass laws that restricted voting rights and undermined public health, and they were less likely to respond to COVID-19. The authors examine the implications for American democracy and for the balance of power between federal and state government; they also offer empirically grounded recommendations for reform.
To describe risk factors associated with inappropriate antibiotic prescribing to children.
Cross-sectional, retrospective analysis of antibiotic prescribing to children, using Kentucky Medicaid medical and pharmacy claims data, 2017.
Population-based sample of pediatric Medicaid patients and providers.
Antibiotic prescriptions were identified from pharmacy claims and used to describe patient and provider characteristics. Associated medical claims were identified and linked to assign diagnoses. An existing classification scheme was applied to determine appropriateness of antibiotic prescriptions.
Overall, 10,787 providers wrote 779,813 antibiotic prescriptions for 328,515 children insured by Kentucky Medicaid in 2017. Moreover, 154,546 (19.8%) of these antibiotic prescriptions were appropriate, 358,026 (45.9%) were potentially appropriate, 163,654 (21.0%) were inappropriate, and 103,587 (13.3%) were not associated with a diagnosis. Half of all providers wrote 12 prescriptions or less to Medicaid children. The following child characteristics were associated with inappropriate antibiotic prescribing: residence in a rural area (odds ratio [OR], 1.09; 95% confidence interval [CI], 1.07–1.1), having a visit with an inappropriate prescriber (OR, 4.15; 95% CI, 4.1–4.2), age 0–2 years (OR, 1.39; 95% CI, 1.37–1.41), and presence of a chronic condition (OR, 1.31; 95% CI, 1.28–1.33).
Inappropriate antibiotic prescribing to Kentucky Medicaid children is common. Provider and patient characteristics associated with inappropriate prescribing differ from those associated with higher volume. Claims data are useful to describe inappropriate use and could be a valuable metric for provider feedback reports. Policies are needed to support analysis and dissemination of antibiotic prescribing reports and should include all provider types and geographic areas.
We describe the frequency of pediatric healthcare-associated infections (HAIs) identified through prospective surveillance in community hospitals participating in an infection control network. Over a 6-year period, 84 HAIs were identified. Of these 51 (61%) were pediatric central-line–associated bloodstream infections, and they often occurred in children <1 year of age.
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
Multiple herbicide-resistant populations of horseweed [Conyza canadensis (L.) Cronquist] continue to spread rapidly throughout Ontario, notably in areas where no-till soybean [Glycine max (L.) Merr.] is grown. The occurrence of multiple herbicide resistance within these populations suggests that the future role of herbicide tank mixtures as a means of control will be limited. An integrated weed management strategy utilizing complementary selection pressures is needed to reduce the selection intensity of relying solely on herbicides for control. Field studies were conducted in 2018 and 2019 to test the hypothesis: if fall-seeded cereal rye (Secale cereale L.) can reduce C. canadensis seedling density and suppress seedling growth, then the interaction(s) of complementary selection pressures of tillage, cereal rye, and herbicides would improve the level of C. canadensis control. Laboratory studies were conducted to determine whether the allelopathic compound 2-benzoxazolinone (BOA) affected the root development of C. canadensis seedlings. The interactions observed among multiple selection pressures of tillage, cereal rye, and herbicides were inconsistent between the 2 yr of study. A monoculture of cereal rye seeded in the fall, however, did reduce seedling height and biomass of C. canadensis consistently, but not density. This reduction in seedling height and biomass was likely caused by the allelopathic compound BOA, which reduced seedling root development. Control of C. canadensis seedlings in the spring required the higher registered rates of dicamba or saflufenacil. The addition of shallow fall tillage and the presence of cereal rye did not improve the variability in control observed notably with 2,4-D or the lower rates of saflufenacil or dicamba. With the implementation of complementary weed management strategies, environmental variables in any given year will likely have a direct influence on whether these interactions are additive or synergistic.
Background: Surgical site infections (SSIs) among cardiothoracic (CT) patients are associated with high rates of morbidity and mortality. Data are limited regarding SSI incidence among pediatric patients undergoing primary reparative procedures for congenital cardiac disease. Published evidence on targeted interventions to prevent pediatric CT-surgery SSI is lacking. We aimed to establish standard metrics for measuring CT-surgery SSI incidence and to implement bundled interventions for SSI prevention. Methods: A dedicated CT-surgery SSI prevention workgroup was established, consisting of hospital leadership, CT surgeons, cardiac critical care unit staff, anesthesia, perfusion, environmental services, instrument sterile processing, risk management, infection prevention and antibiotic stewardship. We created a standard definition for CT-surgery SSI and calculated retrospective SSI rates over a 24-month period (2017–2019). The outcome measured was incidence of CT-surgery SSI per 100 primary cardiac procedures with delayed ( 3 days after primary surgery) or non-delayed chest closure. The difference in proportion of SSI was reported separately for delayed closure and non-delayed closure; statistical significance was tested using a Fisher’s Exact test. We identified many potential improvement opportunities, including gaps in SSI surveillance, poor compliance with daily bathing, inconsistent perioperative antimicrobial prophylaxis, lack of controlled environment for bedside chest closures, and lapses in environmental cleaning. These issues informed the enhanced SSI prevention bundle, which included education on sterility with the operating room (OR) staff. Protocols for care of cardiac patients with delayed chest closures focused on universal daily and preoperative chlorhexidine baths. In addition, the bundle incorporated stringent environmental cleaning interventions including scheduled decluttering of patient rooms and clinical spaces, terminal cleaning of patient rooms prior to returning from the OR, and use of adjunctive ultraviolet light for the daily cleaning of operating rooms and patient rooms at discharge. Results: Surveillance definition of microbiological growth from a clinical sample obtained within 30 days of primary cardiac procedure sufficiently captured all CT-surgery SSIs. Of 551 CT-surgery procedures prior to intervention, 91 (17%) had delayed final operative closures. Prior to the intervention, 16 SSIs were identified from July 2017 – May 2019 for a rate of 2.90 per /100 procedures, and was higher among patients with delayed chest closure 6.59 per /100 procedures (6 SSIs/91 procedures) versus those with primary chest closure 2.17 per /100 procedures (10 SSIs/460 procedures; P = 0.034). Gram-positive organisms, including coagulase coagulase-negative Staphylococci, were most frequently identified as the causative organisms for SSIs. Compliance with bundled intervention, rolled out over a 2-month period, was associated with an immediate decrease in the number of SSIs for primary and delayed chest closures 6SSIs /185 procedures in the initial quarters (August – December 2019) of the post-intervention period. However, this decrease was not reflected in the overall rate (3.24 per /100 procedures) due to fewer procedures performed. Data collection to measure sustainability is ongoing. Conclusions: Bundled interventions targeting skin antisepsis and environmental cleaning may be associated with a decrease in SSIs among pediatric CT-surgery patients. Ongoing surveillance is required to determine sustainability of these interventions.
Matrix positivity is a central topic in matrix theory: properties that generalize the notion of positivity to matrices arose from a large variety of applications, and many have also taken on notable theoretical significance, either because they are natural or unifying. This is the first book to provide a comprehensive and up-to-date reference of important material on matrix positivity classes, their properties, and their relations. The matrix classes emphasized in this book include the classes of semipositive matrices, P-matrices, inverse M-matrices, and copositive matrices. This self-contained reference will be useful to a large variety of mathematicians, engineers, and social scientists, as well as graduate students. The generalizations of positivity and the connections observed provide a unique perspective, along with theoretical insight into applications and future challenges. Direct applications can be found in data analysis, differential equations, mathematical programming, computational complexity, models of the economy, population biology, dynamical systems and control theory.