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There exists a variety of specialized fire dynamics routines, zone fire models, and field fire models. Many of these heuristics and correlations rely on experimental data from fires fueled by gas burners or liquid pool fires and have had minimal, if any, validation against data from fires with solid, more complex fuels, such as upholstered furniture. One hundred and twenty fire experiments were conducted inside a compartment that contained a single ventilation opening in the form of a doorway that was either open or closed for the entirety of each experiment. The fires were fueled by natural gas burners and upholstered furniture items. The compartment was instrumented throughout with thermocouples, oxygen sampling probes, heat flux gauges (total and radiative), pressure transducers, and bi-directional probes. Additionally, heat release rate data were collected during open door experiments with fires larger than 100 kW. This experimental series was designed to better quantify the repeatability of and differences between natural gas burner and upholstered furniture fuels and to provide new validation cases for the fire modeling community.
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Three installation-level lithium-ion battery (LIB) energy storage system (ESS) tests were conducted to the specifications of the UL 9540A standard test method [1]. Each test included a mocked-up initiating ESS unit rack and two target ESS unit racks installed within a standard size 6.06 m (20 ft) International Organization for Standardization (ISO) container. All tests were conducted with an identical LIB configuration. The initiating unit rack included nine modules (2,430 individual 18650 form factor cells) with a total capacity of 28.9 kWh. The target unit racks were loaded to one-third capacity of the initiating unit with nine partial modules and a total capacity of 9.6 kWh. All cells in the container were charged to 100% state-of-charge and none were electrically connected. Within the initiating mock-up unit, a flexible film heater was wrapped around an individual 18650 form factor cell. This instrumented 18650 cell was heated at a rate of 6°C/min to initiate thermal runaway. Test 1 was a baseline performance test and did not utilize any active fire suppression systems. Test 2 included a Novec 1230 system designed for an 8.3 vol% concentration discharged upon activation of two smoke detectors installed inside the container. Test 3 incorporated a dry pipe water suppression system to provide a uniform 20.8 mm/min (0.5 gpm/ft2) spray density delivered at the top of the ESS unit enclosures. Thermocouples were used to measure the cell temperatures in the initiating unit rack and module surface temperatures for the initiating unit and target unit racks. Thermocouples were located throughout the ISO container to measure gas temperatures and wall temperatures. Schmidt-Boelter heat flux gauges were installed to measure incident heat flux to each of the target unit racks as well as the walls adjacent to the initiating rack. Smoke detectors and smoke obscuration meters were used to identify the presence of smoke and characterize opacity of the smoke in the container. Various laboratory- and industrial-grade sensors were used to characterize the gas composition throughout container.
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The fire modeling community currently lacks full-scale data from tests conducted in realistic residential-style structures. Controlled gas burner tests were conducted in purpose-built single- and two-story structures instrumented throughout with thermocouples, pressure transducers, and bi-directional probes. Experiments consisted of sequences of ventilation events. The data collected in these tests was intended to provide several new validation cases for the fire modeling community.
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PURPOSE: To describe opioid prescribing practice patterns and trends in emergency department visits (EDs) by provider type: physicians and advanced practice providers (APPs), which include nurse practitioners (NPs) and physician assistants (PAs). METHODS: The data source was the ED visit files of the 2005-2015 National Hospital Ambulatory Care Survey. The study sample was opioid prescription-related ED visits. Descriptive and multinomial logistic regression analyses were conducted to assess the proportion of opioid prescription-related visits by provider type over time in total and by patient age group. We then characterized opioid prescribing practices of NPs, PAs, and physicians according to type of opioid and pain-related diagnosis. RESULTS: From 2005 to 2015, there was a 116.7% increase in the proportion of the opioid prescription-related visits seen by NPs and a 61.2% increase seen by both APPs and physicians. In contrast, the proportion of the physician-only visits decreased (-8.3%). When stratified by age group, the growth was particularly notable among the visits with patients aged 65 and older seen by both APPs and physicians (AORâ¯=â¯2.35, 95% CIâ¯=â¯1.69, 3.25). Proportionally less hydromorphone and morphine was prescribed by APPs than by physicians. Opioids were prescribed more often by APPs in visits involving dental and injury-related pain, whereas physicians prescribed opioids more in abdominal and chest pain-related visits. CONCLUSIONS: From 2005 to 2015, APPs, particularly NPs played an increasing role in opioid prescribing in EDs. Opioid prescribing practices of APPs and physicians varied by patient condition as well as by opioid type.
Asunto(s)
Analgésicos Opioides/uso terapéutico , Servicio de Urgencia en Hospital/estadística & datos numéricos , Dolor/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Pautas de la Práctica en Medicina/tendencias , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Femenino , Encuestas de Atención de la Salud , Humanos , Hidromorfona/uso terapéutico , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Persona de Mediana Edad , Morfina/uso terapéutico , Enfermeras Practicantes/estadística & datos numéricos , Asistentes Médicos/estadística & datos numéricos , Médicos/estadística & datos numéricos , Estados Unidos , Adulto JovenRESUMEN
Since 1798, the men and women of the Commissioned Corps of the US Public Health Service (USPHS), one of the seven US uniformed services, have served on the front lines of public health. Two hundred years after the start of the USPHS, the first physician assistant (PA) entered the service to carry on the tradition of protecting, promoting, and advancing the health and safety of the nation. These dedicated clinicians are involved in healthcare delivery to underserved and vulnerable populations, disease control and prevention, biomedical research, food and drug regulation, and national and international response efforts for natural and man-made disasters. This article describes how PAs in the Commissioned Corps of the USPHS have impacted the health and safety of not only the United States but also the international community.
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Asistentes Médicos/historia , United States Public Health Service/historia , Atención a la Salud , Femenino , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI , Humanos , Masculino , Salud Pública , Estados UnidosRESUMEN
Comprehensive pyrolysis models that are integral to computational fire codes have improved significantly over the past decade as the demand for improved predictive capabilities has increased. High fidelity pyrolysis models may improve the design of engineered materials for better fire response, the design of the built environment, and may be used in forensic investigations of fire events. A major limitation to widespread use of comprehensive pyrolysis models is the large number of parameters required to fully define a material and the lack of effective methodologies for measurement of these parameters, especially for complex materials. The work presented here details a methodology used to characterize the pyrolysis of a low-pile carpet tile, an engineered composite material that is common in commercial and institutional occupancies. The studied material includes three distinct layers of varying composition and physical structure. The methodology utilized a comprehensive pyrolysis model (ThermaKin) to conduct inverse analyses on data collected through several experimental techniques. Each layer of the composite was individually parameterized to identify its contribution to the overall response of the composite. The set of properties measured to define the carpet composite were validated against mass loss rate curves collected at conditions outside the range of calibration conditions to demonstrate the predictive capabilities of the model. The mean error between the predicted curve and the mean experimental mass loss rate curve was calculated as approximately 20% on average for heat fluxes ranging from 30 to 70 kW·m-2, which is within the mean experimental uncertainty.
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The authors wish to make the following corrections to this manuscript [1]. During the publishing process, symbols that represented the absorption coefficient in Table 4 and thermal conductivity in Table 5 were changed such that they were inconsistent with the rest of the manuscript. [...].