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1.
J Am Chem Soc ; 145(30): 16318-16323, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37486079

RESUMEN

Flammability and combustion of high energy density liquid propellants are controlled by their volatility. We demonstrate a new concept through which the volatility of a high energy density ionic liquid propellant can be dynamically manipulated enabling one to (a) store a thermally insensitive oxidation resistant nonflammable fuel, (b) generate flammable vapor phase species electrochemically by applying a direct-current voltage bias, and (c) extinguish its flame by removing the voltage bias, which stops its volatilization. We show that a thermally stable imidazolium-based energy dense ionic liquid can be made flammable or nonflammable simply by application or withdrawal of a direct-current bias. This cycle can be repeated as often as desired. The estimated energy penalty of the electrochemical activation process is only ∼4% of the total energy release. This approach presents a paradigm shift, offering the potential to make a "safe fuel" or alternatively a simple electrochemically driven fuel metering scheme.

2.
Biotechnol Bioeng ; 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37256724

RESUMEN

An optimal purification process for biopharmaceutical products is important to meet strict safety regulations, and for economic benefits. To find the global optimum, it is desirable to screen the overall design space. Advanced model-based approaches enable to screen a broad range of the design-space, in contrast to traditional statistical or heuristic-based approaches. Though, chromatographic mechanistic modeling (MM), one of the advanced model-based approaches, can be speed-limiting for flowsheet optimization, which evaluates every purification possibility (e.g., type and order of purification techniques, and their operating conditions). Therefore, we propose to use artificial neural networks (ANNs) during global optimization to select the most optimal flowsheets. So, the number of flowsheets for final local optimization is reduced and consequently the overall optimization time. Employing ANNs during global optimization proved to reduce the number of flowsheets from 15 to only 3. From these three, one flowsheet was optimized locally and similar final results were found when using the global outcome of either the ANN or MM as starting condition. Moreover, the overall flowsheet optimization time was reduced by 50% when using ANNs during global optimization. This approach accelerates the early purification process design; moreover, it is generic, flexible, and regardless of sample material's type.

3.
Pediatrics ; 129(1): e165-73, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22144702

RESUMEN

BACKGROUND: Although reports of reduced nosocomial infections (NI) in very low birth weight infants have been published, the durability of these gains and changes in secondary outcomes, and clinical practices have less often been published. METHODS: This was a retrospective, observational study of NI reduction in very low birth weight infants at two hospital campuses. The intervention began in 2005 with our renewed quality improvement efforts to reduce NI. We compared outcomes before (2000-2005) and after (2006-2009) the intervention by using univariate and multiple regression analyses. RESULTS: We reduced NI by 50% comparing 2000-2005 to 2006-2009 (23.6% vs 11.6%, P < .001). Adjusting for covariates, the odds ratio for NI was 0.33 (confidence interval, 0.26 - 0.42, P < .001) in the more recent era. NI were lower even in infants with birth weight 501-1000 grams (odds ratio = 0.38, confidence interval, 0.29 - 0.51, P < .001). We also reduced bronchopulmonary dysplasia (30.2% vs 25.5%, P = .001), median days to regain birth weight (9 vs 8, P = .04), percutaneously placed central venous catheter use (54.8% vs 43.9%, P = .002), median antibiotic days (8 vs 6, P = .003), median total central line days (16 vs 15, P = .01), and median ventilator days (7 vs 5, P = .01). We sustained improvements for three years. CONCLUSIONS: Quality improvement efforts were associated with sustained reductions in NI, bronchopulmonary dysplasia, antibiotic use, central line use, and ventilator days.


Asunto(s)
Infección Hospitalaria/prevención & control , Enfermedades del Prematuro/prevención & control , Recién Nacido de muy Bajo Peso , Mejoramiento de la Calidad , Infecciones Relacionadas con Catéteres/prevención & control , Infección Hospitalaria/etiología , Humanos , Recién Nacido , Recien Nacido Prematuro , Unidades de Cuidado Intensivo Neonatal
4.
J Nurs Care Qual ; 22(1): 73-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17149089

RESUMEN

We describe the development of a database of quality indicators and outcomes for perinatal care as part of a multi-institutional collaborative quality improvement project, Neonatal Intensive Care Quality 2002. Important principles of developing such a database are also discussed including eligibility criteria that identify high-risk patients without burdening data collectors, clinically important and well-defined measures, development of systems within each hospital to ensure identification of all eligible patients, use of data collectors with knowledge of perinatal care, appropriate design of paper and electronic data-collection tools, multiple pilot tests, and periodic feedback of data to participating hospitals.


Asunto(s)
Atención Perinatal/normas , Adulto , Femenino , Humanos , Recién Nacido , Selección de Paciente , Embarazo , Garantía de la Calidad de Atención de Salud
5.
Pediatrics ; 118 Suppl 2: S147-52, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17079617

RESUMEN

OBJECTIVE: The obstetric and neonatal exploratory focus group of the Vermont Oxford Network Neonatal Intensive Care Quality Improvement Collaborative 2002 set out to improve collaboration, communication, and coordination between maternal and neonatal caregivers in 3 areas: the pregnancy at 22 to 26 weeks, measurement of maternal outcomes that are linked with neonatal outcomes, and team performance during high-risk delivery. Antepartum and intrapartum maternal attributes and interventions also were considered important measurements to identify practice variations and their relationship to neonatal outcomes for ongoing obstetric and neonatal collaboration. METHODS: Potentially better practices were developed on the basis of evidence in the literature, expert opinion, and internal analysis at the participating perinatal centers. The potentially better practices include development of local guidelines at each center for the care and counseling of pregnant women who are at risk for delivering at the margin of viability; communication strategies for obstetric and neonatology providers relating to high-risk pregnancy treatment plans; team communication and performance at high-risk deliveries; design of organizational structures and processes that facilitate obstetric and neonatal collaboration; and development of perinatal data to evaluate effects of perinatal practices on maternal, fetal, and neonatal outcomes. RESULTS: As a result of the project, participating centers developed local guidelines for pregnancies between 22 and 26 weeks, created a cross-center maternal database that currently is being linked to neonatal outcomes, and completed a pilot study on video simulation of neonatal-perinatal team communication. CONCLUSIONS: Increased understanding of practice variation in the management of care for infants who are at the margins of viability, locally developed guidelines, and a focus on improved team communication during delivery can be accomplished with a multicenter collaborative approach.


Asunto(s)
Comunicación , Conducta Cooperativa , Neonatología , Obstetricia , Embarazo de Alto Riesgo , Consejo , Bases de Datos como Asunto , Femenino , Grupos Focales , Humanos , Recién Nacido , Capacitación en Servicio , Unidades de Cuidado Intensivo Neonatal/organización & administración , Grupo de Atención al Paciente , Satisfacción del Paciente , Embarazo , Nacimiento Prematuro , Garantía de la Calidad de Atención de Salud , Estados Unidos , Grabación en Video
6.
Pediatrics ; 118 Suppl 2: S169-76, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17079620

RESUMEN

OBJECTIVES: The objective of this study was to determine the attitudes of a variety of health care providers toward the recommendations that should be made to parents regarding the resuscitation of infants who are born at the margins of viability. METHODS: A written questionnaire was distributed to the medical and nursing staff at 4 tertiary perinatal centers. For each of 5 weekly gestational age intervals from 22 weeks to 26 weeks, 6 days, the health care providers were asked to describe on a scale from 1 to 5 whether they would strongly discourage through strongly encourage resuscitation. They also were queried regarding their comfort with counseling regarding these issues. The attitudes of various groups of providers were compared across weekly intervals. RESULTS: A total of 204 physicians and 539 nurses completed the survey. The majority would strongly discourage, either discourage or strongly discourage, be neutral or recommend, recommend or strongly recommend, and strongly recommend resuscitation during the 23rd, 24th, 25th, 26th, and 27th weeks of gestation, respectively. Obstetric caregivers were slightly less likely than pediatric caregivers to strongly discourage resuscitation from 22 weeks to 22 weeks, 6 days and 23 weeks to 23 weeks, 6 days. There were no significant differences in the recommendations of obstetricians and pediatricians. Pediatric nurses were more likely to strongly recommend resuscitation from 26 weeks to 26 weeks, 6 days and more likely either to discourage or to strongly discourage resuscitation from 23 weeks to 23 weeks, 6 days and to strongly discourage resuscitation from the 22 weeks to 22 weeks, 6 days than their obstetric counterparts. Obstetric nurses were slightly less likely than obstetricians to strongly recommend resuscitation at 26 weeks to 26 weeks, 6 days and less likely to strongly discourage resuscitation from 22 weeks to 22 weeks, 6 days. CONCLUSIONS: The caregivers' recommendations seem to be based logically on the current literature regarding survival and morbidity that is experienced by infants who are born at the threshold of viability. Although there are minor differences, there was a relatively consistent approach among professional groups.


Asunto(s)
Actitud del Personal de Salud , Edad Gestacional , Recien Nacido Prematuro , Cuidado Intensivo Neonatal , Resucitación , Consejo , Humanos , Recién Nacido , Enfermería Obstétrica , Obstetricia , Enfermería Pediátrica , Pediatría , Encuestas y Cuestionarios , Estados Unidos
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