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1.
J Chem Phys ; 129(23): 234709, 2008 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-19102554

RESUMEN

Stacked AA graphite has been synthesized using a high-density dc plasma in hydrogen-methane mixtures. Graphene layers have been grown epitaxially with 2-1 registration between the AA graphitic edges and the (111) surface of diamond. In addition, a new graphite crystal structure containing AA(') graphene layers, where alternate planes are translated by half the hexagon width, is formed by 1-1 registry. The resulting interplanar distances of the AA graphite at the interface range from 2.20 A for the 1-1 registration to 4.40 A for the 2-1 registration and have been measured directly by high-resolution transmission electron microscopy (TEM). The appearance of the characteristic d-spacings, 3.55, 2.15, 1.80, 1.75 (not fully resolved), and 1.25 A in the selective area diffraction patterns from the TEM, are consistent with reflections from the (001), (100), (102), (002), and (110) planes of the AA graphite. Simulation of the diffraction patterns, employing the structural factors of graphene, confirms the existence of AA graphite.

2.
Heart ; 99(1): 35-40, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23002253

RESUMEN

OBJECTIVE: To evaluate the performance of the National Institute for Health and Clinical Excellence (NICE) mini-Global Registry of Acute Coronary Events (GRACE) (MG) and adjusted mini-GRACE (AMG) risk scores. DESIGN: Retrospective observational study. SETTING: 215 acute hospitals in England and Wales. PATIENTS: 137 084 patients discharged from hospital with a diagnosis of acute myocardial infarction (AMI) between 2003 and 2009, as recorded in the Myocardial Ischaemia National Audit Project (MINAP). MAIN OUTCOME MEASURES: Model performance indices of calibration accuracy, discriminative and explanatory performance, including net reclassification index (NRI) and integrated discrimination improvement. RESULTS: Of 495 263 index patients hospitalised with AMI, there were 53 196 ST elevation myocardial infarction and 83 888 non-ST elevation myocardial infarction (NSTEMI) (27.7%) cases with complete data for all AMG variables. For AMI, AMG calibration was better than MG calibration (Hosmer-Lemeshow goodness of fit test: p=0.33 vs p<0.05). MG and AMG predictive accuracy and discriminative ability were good (Brier score: 0.10 vs 0.09; C statistic: 0.82 and 0.84, respectively). The NRI of AMG over MG was 8.1% (p<0.05). Model performance was reduced in patients with NSTEMI, chronic heart failure, chronic renal failure and in patients aged ≥85 years. CONCLUSIONS: The AMG and MG risk scores, utilised by NICE, demonstrated good performance across a range of indices using MINAP data, but performed less well in higher risk subgroups. Although indices were better for AMG, its application may be constrained by missing predictors.


Asunto(s)
Academias e Institutos , Infarto del Miocardio/diagnóstico , Evaluación de Resultado en la Atención de Salud/métodos , Medición de Riesgo , Anciano , Inglaterra/epidemiología , Femenino , Humanos , Masculino , Auditoría Médica , Infarto del Miocardio/clasificación , Infarto del Miocardio/mortalidad , Pronóstico , Sistema de Registros , Reproducibilidad de los Resultados , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad , Tasa de Supervivencia , Factores de Tiempo , Gales/epidemiología
3.
Eur Heart J Acute Cardiovasc Care ; 2(1): 9-18, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24062929

RESUMEN

AIM: To investigate whether a hospital-specific opportunity-based composite score (OBCS) was associated with mortality in 136,392 patients with acute myocardial infarction (AMI) using data from the Myocardial Ischaemia National Audit Project (MINAP) 2008-2009. METHODS AND RESULTS: For 199 hospitals a multidimensional hospital OBCS was calculated on the number of times that aspirin, thienopyridine, angiotensin-converting enzyme inhibitor (ACEi), statin, ß-blocker, and referral for cardiac rehabilitation was given to individual patients, divided by the overall number of opportunities that hospitals had to give that care. OBCS and its six components were compared using funnel plots. Associations between OBCS performance and 30-day and 6-month all-cause mortality were quantified using mixed-effects regression analysis. Median hospital OBCS was 95.3% (range 75.8-100%). By OBCS, 24.1% of hospitals were below funnel plot 99.8% CI, compared to aspirin (11.1%), thienopyridine (15.1%), ß-blockers (14.7%), ACEi (19.1%), statins (12.1%), and cardiac rehabilitation (17.6%) on discharge. Mortality (95% CI) decreased with increasing hospital OBCS quartile at 30 days [Q1, 2.25% (2.07-2.43%) vs. Q4, 1.40% (1.25-1.56%)] and 6 months [Q1, 7.93% (7.61-8.25%) vs. Q4, 5.53% (5.22-5.83%)]. Hospital OBCS quartile was inversely associated with adjusted 30-day and 6-month mortality [OR (95% CI), 0.87 (0.80-0.94) and 0.92 (0.88-0.96), respectively] and persisted after adjustment for coronary artery catheterization [0.89 (0.82-0.96) and 0.95 (0.91-0.98), respectively]. CONCLUSIONS: Multidimensional hospital OBCS in AMI survivors are high, discriminate hospital performance more readily than single performance indicators, and significantly inversely predict early and longer-term mortality.

4.
New Dir Youth Dev ; (110): 149-54, 21-2, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17017265

RESUMEN

The motivation behind every educator's dedication and hard work in the classroom is the knowledge that his or her teaching will result in students' success in life. Educators are committed to implementing twenty-first century skills; they have no question that students need such skills to be equipped for life beyond school. Members of the National Education Association are enthusiastic about the Partnership for 21st Century Skills framework, yet express frustration that many schools do not have adequate resources to make the necessary changes. Teaching these skills poses significant new responsibilities for schools and educators. To make it possible for teachers to build twenty-first century skills into the curriculum, physical and policy infrastructures must exist, professional development and curriculum materials must be offered, and meaningful assessments must be available. With an established understanding of what skills need to be infused into the classroom-problem solving, analysis, and com- munications-and educators' commitment to the new skill set, this chapter explores how to make such a dramatic reform happen. The author discusses existing strategies that will guide educators in infusing twenty-first century skills into traditional content areas such as math, English, geography, and science. Ultimately, public policy regarding educational standards, professional development, assessments, and physical school structures must exist to enable educators to employ twenty-first century skills, leading to student success in contemporary life. Any concern about the cost of bringing this nation's educational system up to par internationally should be offset by the price that not making twenty-first century skills a priority in the classroom will have on future economic well-being.


Asunto(s)
Logro , Educación Profesional , Aprendizaje , Instituciones Académicas , Enseñanza/normas , Adolescente , Adulto , Niño , Educación Profesional/tendencias , Predicción , Humanos , Estados Unidos
5.
J Am Chem Soc ; 125(22): 6600-1, 2003 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-12769547

RESUMEN

Microwave plasma deposited (100) diamond films have been thermally oxidized in dry O2 between 500 and 723 degrees C. The roughness of a single crystalline grain following oxidation is consistent with a layer-by-layer mechanism for the removal of carbon monoxide. The resulting surface exhibits infrared absorption bands at 1731 and 905 cm-1, attributed to the stretching and bending modes of a surface bonded carbonyl group. The former is within 1 cm-1 of the structurally analogous molecule 2-adamantanone. These data are consistent with the carbonyl groups being present on diamond (100) terraces.

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