All-aromatic biphenylene end-capped polyquinoline and polyimide matrix resins

Biphenylene end-capped polyquinoline and polyimide resins afford low void content graphite-reinforced composites with good initial properties. However, with both resins, rapid degradation occurs during oxidative isothermal aging at elevated temperatures. The degradation is not observed during isothermal aging under a nitrogen atmosphere which suggests that the biphenylene end-cap (or the resulting crosslink/chain extension structures) is not particularly thermooxidatively stable. The nature of the thermooxidative instability is currently under investigation

d13C tracing of dissolved inorganic carbon sources in Patagonian rivers (Argentina)

The main Patagonian rivers (Colorado, Negro, Chubut, Deseado, Coyle, Chico, Santa Cruz and Gallegos) were sampled between September 1995 and November 1998 to determine their chemical and isotopic compositions, the origins of the suspended and dissolved river loads and their inputs to the South Atlantic Ocean. This paper focuses on the dissolved inorganic carbon (DIC) transport and its υ13C isotopic signature. The υ13CDIC values vary between 12Ð8 and 1Ð8‰ and allow one to distinguish two river groups: (i) the Colorado, Negro, Chubut and Santa Cruz, which display the highest values and the lowest seasonal variations; (ii) the Deseado, Coyle, Chico and Gallegos, which show the lowest values and the highest seasonal variations. For the first group, υ13CDIC is mainly controlled by important exchanges between the river waters and atmospheric CO2, due to the presence of lakes and dams. For the second group, υ13CDIC also appears to be controlled by the oxidation of organic carbon, showing a negative relationship between υ13CDIC and the dissolved organic carbon. These biogeochemical processes interfere with the contribution of carbonate and silicate weathering to the riverine DIC and do not allow use of υ13CDIC alone to distinguish these contributions. The annual DIC flux exported by Patagonian Rivers to the South Atlantic Ocean averages 621 ð 109 g. of C, i.e. a specific yield of 2Ð7 g m2 year1. The mean υ13CDIC can be estimated to 4Ð9‰, which is high compared with other rivers of the world

Enhancing Collaboration Between Primary and Subspeciality Care Providers for Children and Youth with Special Health Care Needs

Summary: The goals of this guide are to discuss the complementary roles of generalist and subspecialist physicians in providing coordinated and effective care for children and youth with special health care needs. We will emphasize the centrality of family-professional partnerships. We also will describe various models for collaboration among generalist and subspecialist physicians and families. Ultimately, the value of this guide will be to serve as a framework for discussion about how primary and subspecialty care physicians can work collaboratively to enhance the quality of care that children and youth with special health care needs and their families receive

Technology Assessment for Large Vertical-Lift Transport Tiltrotors

The technical community has identified rotor efficiency as a critical enabling technology for large vertical-lift transport (LVLT) rotorcraft. The size and performance of LVLT aircraft will be far beyond current aircraft capabilities, enabling a transformational change in cargo transport effectiveness. Two candidate approaches for achieving high efficiency were considered for LVLT applications: a variable-diameter tiltrotor (VDTR) and a variable-speed tiltrotor (VSTR); the former utilizes variable-rotor geometry and the latter utilizes variable-rotor speed. Conceptual aircraft designs were synthesized for the VDTR and VSTR and compared to a conventional tiltrotor (CTR). The aircraft were optimized to a common objective function and bounded by a set of physical- and requirements-driven constraints. The resulting aircraft were compared for weight, size, performance, handling qualities, and other attributes. These comparisons established a measure of the relative merits of the variable-diameter and -speed rotor systems as enabling technologies for LVLT capability

Using Home Visits to Understand Medication Errors in Children

Summary: Current research methods are not well designed to detect medication errors that occur at home. We developed home visit methods to investigate home medication errors in children with chronic conditions. These methods include observation of parent administration of medication to the child by a trained nurse observer who takes detailed ethnographic notes; review of all prescription and over-the-counter medications for dispensing errors, pill counts, and medication reconciliation; and parent interviews to identify barriers to effective home use of medications, prior home medication errors that parents are aware of, and suggestions for systemic improvements. Details about each possible error detected are recorded using a structured data collection form (allergies, medication list, dispensing errors, administration errors). We conducted several pilot home visits and found that this approach has the potential to help understand home medication errors in order to develop interventions to improve the safety of medication self-management

Care Coordination for Children With Medical Complexity: Whose Care Is It, Anyway?

Children with medical complexity (CMC) have multiple chronic conditions and require an array of medical- and community-based providers. Dedicated care coordination is increasingly seen as key to addressing the fragmented care that CMC often encounter. Often conceptually misunderstood, care coordination is a team-driven activity that organizes and drives service integration. In this article, we examine models of care coordination and clarify related terms such as care integration and case management. The location of care coordination resources for CMC may range from direct practice provision to external organizations such as hospitals and accountable care organizations. We discuss the need for infrastructure building, design and implementation leadership, use of care coordination tools and training modules, and appropriate resource allocation under new payment models

Methodological Challenges in Describing Medication Dosing Errors in Children

Summary: Although children are prescribed medications in 30 percent to 50 percent of clinic visits, little is known about medication errors in ambulatory pediatrics. In the process of completing a study to determine the prevalence of outpatient dosing errors, we identified a number of barriers to understanding the epidemiology of medication errors in children. These barriers include prescribing medication that is not labeled for use in children, discrepancies in published dosing recommendations for many medications, unclear guidelines on use of adult dosing recommendations for children of different ages and weights, and the lack of readily available documented weights to determine appropriate weight-based doses for children. In our study of pediatric medication errors, we found a wide range of doses prescribed to children for every medication we studied. Before we can truly understand medication errors in children and begin developing systems-based approaches to eliminating these errors, we need better national standards of medication doses that are appropriate for children and an improved ability to determine errors through databases that include children\u27s weights as well as prescription information