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In the market for next-generation energy storage, lithium-sulfur (Li-S) technology is one of the most promising candidates due to its high theoretical specific energy and cost-efficient ubiquitous active materials. In this study, this cell system was combined with a cost-efficient sustainable solvent-free electrode dry-coating process (DRYtraec®). So far, this process has been only feasible with polytetrafluoroethylene (PTFE)-based binders. To increase the sustainability of electrode processing and to decrease the undesired fluorine content of Li-S batteries, a renewable, biodegradable, and fluorine-free polypeptide was employed as a binder for solvent-free electrode manufacturing. The yielded sulfur/carbon dry-film cathodes were electrochemically evaluated under lean electrolyte conditions at coin and pouch cell level, using the state-of-the-art 1,2-dimethoxyethane/1,3-dioxolane electrolyte (DME/DOL) as well as the sparingly polysulfide-solvating electrolytes hexylmethylether (HME)/DOL and tetramethylene sulfone/1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TMS/TTE). These results demonstrated that the PTFE binder can be replaced by the biodegradable sericin as the cycle stability and performance of the cathodes was retained.
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Litio , Azufre , Litio/química , Solventes , Electrodos , Azufre/química , Electrólitos/química , PolitetrafluoroetilenoRESUMEN
Electrification is progressing significantly within the present and future vehicle sectors such as large commercial vehicles (e.g., trucks and buses), high-altitude long endurance (HALE), high-altitude pseudosatellites (HAPS), and electric vertical take-off and landing (eVTOL). The battery systems' performance requirements differ across these applications in terms of power, cycle life, system cost, etc. However, the need for high gravimetric energy density, 400 Wh kg-1 and beyond, is common across them all, as it enables vehicles to achieve extended range, a longer mission duration, lighter weight, or increased payload. The system-level requirements of these emerging applications are broken down into the component-level developments required to integrate Li-S technology as the power system of choice. To adapt batteries' properties, such as energy and power density, to the respective application, the academic research community has a key role to play in component-level development. However, materials and component research must be conducted within the context of a viable Li-S cell system. Herein, the key performance benefits, limitations, modeling, and recent progress of the Li-S battery technology and its adaption toward real-world application are discussed.
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BACKGROUND: Multiple registries have reported that >40% of high-risk atrial fibrillation patients are not taking oral anticoagulants. The purpose of our study was to determine the presence or absence of active atrial fibrillation and CHA2DS2-VASc (Congestive heart failure, Hypertension, Age ≥75 y, Diabetes mellitus, prior Stroke [or transient ischemic attack or thromboembolism], Vascular disease, Age 65-74 y, Sex category) risk factors to accurately identify high-risk atrial fibrillation (CHA2DS2-VASc ≥2) patients requiring oral anticoagulants and the magnitude of the anticoagulant treatment gap. METHODS: We retrospectively adjudicated 6514 patients with atrial fibrillation documented by at least one of: billing diagnosis, electronic medical record encounter diagnosis, electronic medical record problem list, or electrocardiogram interpretation. RESULTS: After review, 4555/6514 (69.9%) had active atrial fibrillation, while 1201 had no documented history of atrial fibrillation and 758 had a history of atrial fibrillation that was no longer active. After removing the 1201 patients without a confirmed atrial fibrillation diagnosis, oral anticoagulant use in high-risk patients increased to 71.1% (P < .0001 compared with 62.9% at baseline). Oral anticoagulant use increased to 79.7% when the 758 inactive atrial fibrillation patients were also eliminated from the analysis (P < .0001 compared with baseline). In the active high-risk atrial fibrillation group, there was no significant difference in the use of oral anticoagulants between men (80.7%) and women (78.8%) with a CHA2DS2-VASc ≥2, or in women with a CHA2DS2-VASc ≥3 (79.9%). CONCLUSIONS: Current registries and health system health records with unadjudicated diagnoses over-report the number of high-risk atrial fibrillation patients not taking oral anticoagulants. Expert adjudication identifies a smaller treatment gap than previously described.
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Fibrilación Atrial/tratamiento farmacológico , Inhibidores del Factor Xa/administración & dosificación , Reacciones Falso Positivas , Medición de Riesgo/métodos , Factores de Edad , Anciano , Anciano de 80 o más Años , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/fisiopatología , Coagulación Sanguínea/efectos de los fármacos , Inhibidores del Factor Xa/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Sistema de Registros/estadística & datos numéricos , Estudios Retrospectivos , Medición de Riesgo/normas , Medición de Riesgo/estadística & datos numéricos , Factores de Riesgo , Factores Sexuales , Tromboembolia/tratamiento farmacológico , Tromboembolia/prevención & controlRESUMEN
OBJECTIVE: To examine the role of the CHA2DS2-VASc (Congestive heart failure; Hypertension; Age ≥75 years [doubled]; Diabetes; previous Stroke, transient ischemic attack, or thromboembolism [doubled]; Vascular disease; Age 65-75 years; and Sex category) score as a prognostic marker of in-hospital mortality in critically ill patients who develop new-onset atrial fibrillation (NOAF). DESIGN: Retrospective analyses. SETTING: A single-center study in a tertiary care academic medical center. PARTICIPANTS: The study comprised all adult patients with NOAF admitted to noncardiac intensive care units (ICUs) at a tertiary care academic institution between January 2009 and March 2016. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors retrospectively reviewed electronic medical records of all adult patients admitted to noncardiac ICUs at a tertiary care academic institution between January 2009 and March 2016. Patients with NOAF were identified and their CHA2DS2-VASc score was calculated. The authors evaluated the association of CHA2DS2-VASc score and its individual components with in-hospital mortality in these patients. A total of 640 (1.7% [38,708 patients]; 95% CI 1.5%-1.8%) patients developed NOAF during the study period. The in-hospital mortality rate in patients included in the analysis was 14.3%. There was no association between in-hospital mortality and CHA2DS2VASc score. However, the likelihood of in-hospital death was 1.56⯠timesâ¯greater for patients having atrial fibrillation and concomitant vascular disease (95% CI 1.003-2.429; pâ¯=â¯0.049). CONCLUSIONS: New-onset atrial fibrillation is common in critically ill patients and is associated with high in-hospital mortality. The authors found that the CHA2DS2-VASc score itself is not a reliable prognostic marker of in-hospital mortality in these patients. However, the presence of vascular disease in patients with NOAF may increase the mortality associated with this disease.
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Fibrilación Atrial , Accidente Cerebrovascular , Adulto , Anciano , Fibrilación Atrial/diagnóstico , Enfermedad Crítica , Mortalidad Hospitalaria , Humanos , Estudios Retrospectivos , Medición de Riesgo , Factores de RiesgoRESUMEN
Lithium-sulfur batteries can displace lithium-ion by delivering higher specific energy. Presently, however, the superior energy performance fades rapidly when the sulfur electrode is loaded to the required levels-5 to 10 mg cm-2- due to substantial volume change of lithiation/delithiation and the resultant stresses. Inspired by the classical approaches in particle agglomeration theories, we found an approach that places minimum amounts of a high-modulus binder between neighboring particles, leaving increased space for material expansion and ion diffusion. These expansion-tolerant electrodes with loadings up to 15 mg cm-2 yield high gravimetric (>1200 mA·hour g-1) and areal (19 mA·hour cm-2) capacities. The cells are stable for more than 200 cycles, unprecedented in such thick cathodes, with Coulombic efficiency above 99%.
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Despite a high incidence of new onset atrial fibrillation (NOAF) in critically ill patients and its association with short and long-term incidence of stroke, there is limited data assessing anticoagulation on hospital discharge in these patients. We retrospectively reviewed electronic medical records of all adult patients admitted to non-cardiac ICUs at our institution between January 2009 and March 2016. Patients with NOAF were identified and CHA2DS2-VASc score of ICU survivors was calculated. Prescription of oral anticoagulant therapy on hospital discharge was analyzed. A total of 640 (1.7% [38,708 patients]; 95% CI 1.5%, 1.8%) patients developed NOAF during the study period. CHA2DS2-VASc score was calculated for 615 patients, of which 82.2% had a CHA2DS2-VASc score ≥ 2. Of the 428 eligible patients, only 96 patients (22.4%) were discharged on oral anticoagulant therapy. Patients with a history of congestive heart failure (33.7% vs. 19.7%) and stroke/TIA or other thromboembolic disease (35.9% vs. 18.0%) were more likely to be discharged on an oral anticoagulant. Patients with a higher score were also more likely to be discharged on an oral anticoagulant (OR 1.27; 95% CI 1.10, 1.47). NOAF is common in critically ill patients admitted to non-cardiac ICUs and a significant proportion of these patients have a CHA2DS2-VASc score ≥ 2. However, only a minority of them are discharged on an oral anticoagulant. There is a need to identify ways to improve implementation of effective stroke prophylaxis in these patients.
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Fibrilación Atrial/tratamiento farmacológico , Premedicación/métodos , Accidente Cerebrovascular/prevención & control , Adulto , Anciano , Anticoagulantes/uso terapéutico , Fibrilación Atrial/complicaciones , Enfermedad Crítica , Registros Electrónicos de Salud , Femenino , Humanos , Unidades de Cuidados Intensivos , Masculino , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
BACKGROUND: Many academic hospitals have implemented overnight hospitalists to supervise house staff and improve outcomes, but few studies have described the impact of this role. OBJECTIVE: To investigate the effect of an overnight academic hospitalist program on patient-level outcomes. Secondary objectives were to describe the program's revenue generation and work tasks. DESIGN: Retrospective interrupted time-series analysis of patients admitted to the medicine service before and after implementation of the program. PARTICIPANTS: All patients aged 18 and older admitted to the acute or intermediate care units between 7:00 p.m. and 6:59 a.m. during the period before (April 2011-August 2012) and after (September 2012-April 2014) program implementation. INTERVENTION: An on-site attending-level physician directly supervising medicine house staff overnight, providing clinical care during high-volume periods, and ensuring safe handoffs to daytime providers. MAIN MEASURES: Primary outcomes included in-hospital mortality, 30-day hospital readmissions, length of stay, and upgrades in care on the night of admission and during hospitalization. Multivariable models estimated the effect on outcomes after adjusting for secular trends. Revenue generation and work tasks are reported descriptively. KEY RESULTS: During the study period, 6484 patients were admitted to the medicine service: 2722 (42 %) before and 3762 (58 %) after implementation. No differences were found in mortality (1.1 % vs. 0.9 %, p=0.38), 30-day readmissions (14.8 % vs. 15.6 %, p=0.39), mean length of stay (3.09 vs. 3.08 days, p=0.86), or upgrades to intensive care on the night of admission (0.4 % vs. 0.7 %, p=0.11) or during hospitalization (3.5 % vs. 4.2 %, p=0.20). During the first year, hospitalists billed 1209 patient encounters (3.3/shift) and 63 procedures (0.2/shift), and supervised 1939 patient admissions (6.12/shift) while supervising house staff 3-h/shifts. CONCLUSIONS: Implementation of an overnight academic hospitalist program showed no impact on several important clinical outcomes, and revenue generation was modest. As overnight hospitalist programs develop, investigations are needed to delineate the return on investment and focus on other outcomes that may be more sensitive to change, such as errors and provider/patient satisfaction.
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Atención Posterior/organización & administración , Médicos Hospitalarios/organización & administración , Centros Médicos Académicos/economía , Centros Médicos Académicos/organización & administración , Adolescente , Adulto , Anciano , Femenino , Investigación sobre Servicios de Salud/métodos , Precios de Hospital/estadística & datos numéricos , Mortalidad Hospitalaria , Hospitalización , Humanos , Medicina Interna/organización & administración , Tiempo de Internación/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Evaluación del Resultado de la Atención al Paciente , Readmisión del Paciente/estadística & datos numéricos , Pennsylvania/epidemiología , Evaluación de Programas y Proyectos de Salud , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Computerized physician order entry (CPOE) systems are quickly becoming ubiquitous, and groups of orders ("order sets") to allow for easy order input are a common feature. This provides a streamlined mechanism to view, modify, and place groups of related orders. This often serves as an electronic equivalent of a specialty requisition. A characteristic, of these order sets is that specific orders can be predetermined to be "preselected" or "defaulted-on" whenever the order set is used while others are "optional" or "defaulted-off" (though there is typically the option is to "deselect" defaulted-on tests in a given situation). While it seems intuitive that the defaults in an order set are often accepted, additional study is required to understand the impact of these "default" settings in an order set on ordering habits. This study set out to quantify the effect of changing the default settings of an order set. METHODS: For quality improvement purposes, order sets dealing with transfusions were recently reviewed and modified to improve monitoring of outcome. Initially, the order for posttransfusion hematocrits and platelet count had the default setting changed from "optional" to "preselected." The default settings for platelet count was later changed back to "optional," allowing for a natural experiment to study the effect of the default selections of an order set on clinician ordering habits. RESULTS: Posttransfusion hematocrit values were ordered for 8.3% of red cell transfusions when the default order set selection was "off" and for 57.4% of transfusions when the default selection was "preselected" (P < 0.0001). Posttransfusion platelet counts were ordered for 7.0% of platelet transfusions when the initial default order set selection was "optional," increased to 59.4% when the default was changed to "preselected" (P < 0.0001), and then decreased to 7.5% when the default selection was returned to "optional." The posttransfusion platelet count rates during the two "optional" periods: 7.0% versus 7.5% - were not statistically different (P = 0.620). DISCUSSION: Default settings in CPOE order sets can significantly influence physician selection of laboratory tests. Careful consideration by all stakeholders, including clinicians and pathologists, should be obtained when establishing default settings in order sets.