Search

We have determined the complex dielectric tensor of single crystalline 3,4,9,10-perylene tetracarboxylic dianhydride (α-PTCDA) as a function of energy in the range between 1.4 and 5.0 eV. The results obtained reflect the monoclinic symmetry of the crystal: The principal axes of the real and the imaginary part of the tensor in general do not coincide and show chromatic dispersion. Monoclinic behavior allows rotation of the components ɛX and ɛZ in the plane perpendicular to the unique symmetry axis Y. The experimental results indicate that the energies of the optical transitions observed in the weak ɛX component coincide with energies in which a resonance effect due to coupling with the stronger ɛZ component occurs. These resonances appear at energies close to electronic excitations such as the optical gap, the transport gap and the highest occupied molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) peak-to-peak gap and their assignments are discussed based on theoretical calculations.

Objective To compare the clinical characteristics and outcomes of patients with acute heart failure (AHF) according to clinical profiles based on congestion and perfusion determined in the emergency department (ED). Methods and results Overall, 11 261 unselected AHF patients from 41 Spanish EDs were classified according to perfusion (normoperfusion = warm; hypoperfusion = cold) and congestion (not = dry; yes = wet). Baseline and decompensation characteristics were recorded as were the main wards to which patients were admitted. The primary outcome was 1-year all-cause mortality; secondary outcomes were need for hospitalisation during the index AHF event, in-hospital all-cause mortality, prolonged hospitalisation, 7-day post-discharge ED revisit for AHF and 30-day post-discharge rehospitalisation for AHF. A total of 8558 patients (76.0%) were warm+ wet, 1929 (17.1%) cold+ wet, 675 (6.0%) warm+ dry, and 99 (0.9%) cold+ dry; hypoperfused (cold) patients were more frequently admitted to intensive care units and geriatrics departments, and warm+ wet patients were discharged home without admission. The four phenotypes differed in most of the baseline and decompensation characteristics. The 1-year mortality was 30.8%, and compared to warm+ dry, the adjusted hazard ratios were significantly increased for cold+ wet (1.660; 95% confidence interval 1.400-1.968) and cold+ dry (1.672; 95% confidence interval 1.189-2.351). Hypoperfused (cold) phenotypes also showed higher rates of index episode hospitalisation and in-hospital mortality, while congestive (wet) phenotypes had a higher risk of prolonged hospitalisation but decreased risk of rehospitalisation. No differences were observed among phenotypes in ED revisit risk. Conclusions Bedside clinical evaluation of congestion and perfusion of AHF patients upon ED arrival and classification according to phenotypic profiles proposed by the latest European Society of Cardiology guidelines provide useful complementary information and help to rapidly predict patient outcomes shortly after ED patient arrival.

Objective: To assess the effects of non-invasive ventilation (NIV) in emergency department (ED) patients with acute heart failure (AHF) on short term outcomes. Methods: Patients from the EAHFE Registry (a multicenter, observational, multipurpose, cohort-designed database including consecutive AHF patients in 41 Spanish EDs) were grouped based on NIV treatment (NIV+ and NIV–groups). Using propensity score (PS) methodology, we identified two subgroups of patients matched by 38 covariates and compared regarding 30-day survival (primary outcome). Interaction was investigated for age, sex, ischemic cardiomyopathy, chronic obstructive pulmonary disease, AHF precipitated by an acute coronary syndrome (ACS), AHF classified as hypertensive or acute pulmonary edema (APE), and systolic blood pressure (SBP). Secondary outcomes were intensive care unit (ICU) admission; mechanical ventilation; in-hospital, 3-day and 7-day mortality; and prolonged hospitalization (>7 days). Results: Of 11, 152 patients from the EAHFE (age (SD): 80 (10) years; 55.5% women), 718 (6.4%) were NIV+ and had a higher 30-day mortality (HR = 2.229; 95%CI = 1.861–2.670) (p < 0.001). PS matching provided 2 groups of 490 patients each with no significant differences in 30-day mortality (HR = 1.239; 95%CI = 0.905–1.696) (p = 0.182). Interaction analysis suggested a worse effect of NIV on elderly patients (>85 years, p < 0.001), AHF associated with ACS (p = 0.045), and SBP < 100 mmHg (p < 0.001). No significant differences were found in the secondary endpoints except for more prolonged hospitalizations in NIV+ patients (OR = 1.445; 95%CI = 1.122–1.862) (p = 0.004). Conclusion: The use of NIV to treat AHF in ED is not associated with improved mortality outcomes and should be cautious in old patients and those with ACS and hypotension.

Objective: To investigate the relationship between length of hospitalisation (LOH) and post-discharge outcomes in acute heart failure (AHF) patients and to ascertain whether there are different patterns according to department of initial hospitalisation. Methods: Consecutive AHF patients hospitalised in 41 Spanish centres were grouped based on the LOH (< 6/6-10/11-15/ > 15 days). Outcomes were defined as 90-day post-discharge all-cause mortality, AHF readmissions, and the combination of both. Hazard ratios (HRs), adjusted by chronic conditions and severity of decompensation, were calculated for groups with LOH > 6 days vs. LOH < 6 days (reference), and stratified by hospitalisation in cardiology, internal medicine, geriatrics, or short-stay units. Results: We included 8563 patients (mean age: 80 (SD = 10) years, 55.5% women), with a median LOH of 7 days (IQR 4-11): 2934 (34.3%) had a LOH < 6 days, 3184 (37.2%) 6-10 days, 1287 (15.0%) 11-15 days, and 1158 (13.5%) > 15 days. The 90-day post-discharge mortality was 11.4%, readmission 32.2%, and combined end-point 37.4%. Mortality was increased by 36.5% (95%CI = 13.0-64.9) when LOH was 11-15 days, and by 72.0% (95%CI = 42.6-107.5) when > 15 days. Conversely, no differences were found in readmission risk, and the combined end-point only increased 21.6% (95%CI = 8.4-36.4) for LOH > 15 days. Stratified analysis by hospitalisation departments rendered similar post-discharge outcomes, with all exhibiting increased mortality for LOH > 15 days and no significant increments in readmission risk. Conclusions: Short hospitalisations are not associated with worse outcomes. While post-discharge readmissions are not affected by LOH, mortality risk increases as the LOH lengthens. These findings were similar across hospitalisation departments.

Objetivo: Dado el actual desajuste existente entre oferta y demanda de médicos especialistas en el sistema sanitario español, el objetivo de este trabajo es mostrar el impacto que puede tener sobre el sistema las actuales políticas de convocatoria de plazas de formación médica especializada -plazas MIR-, así como diversas medidas y políticas alternativas de control. Métodos: Con esta finalidad se procedió a elaborar un modelo de simulación del proceso de convocatoria de plazas empleando como metodología la dinámica de sistemas. A partir del modelo elaborado y validado, se procede a simular la posible evolución del sistema a lo largo del tiempo ante diversas políticas de convocatoria. En concreto, se observa la evolución de la bolsa histórica de licenciados sin especialidad, la bolsa de médicos especialistas y el gap, o desajuste, entre oferta y demanda, existente en el período de simulación considerado. Resultados: De los resultados obtenidos de la simulación se observa que una política de convocatoria como la actual tiende a reducir la bolsa histórica de licenciados sin especialidad, debido a la propia filosofía que caracteriza a la actual convocatoria, pero incrementa considerablemente la bolsa de médicos especialistas y agudiza el desequilibrio existente. Esta tendencia se mantiene a pesar de que se adopten en la simulación medidas más restrictivas en numerus clausus y edad de jubilación forzosa. Se observa igualmente cómo una política consciente de las necesidades sociales y de los retrasos formativos existentes en el proceso mejora de modo sustancial la evolución, eliminando con el tiempo la bolsa de médicos especialistas y el desequilibrio. Si a su vez se combina dicha política con las medidas anteriormente citadas, los resultados obtenidos son aún superiores, eliminando ambas bolsas y el desajuste existente con mayor rapidez. Conclusiones: Si la Administración Sanitaria continúa convocando plazas de especialización como hasta el presente se agudizarán los problemas de desequilibrio existentes. Por lo tanto, es preciso adoptar medidas y políticas más previsoras con visión a largo plazo, así como una mayor coordinación entre la formación pre y posgraduada. Objective: Currently there is a large imbalance between supply and demand for medical specialists in the Spanish Health System. The aim of this study was to demonstrate the possible effects of current policies of allocating vacancies for interns and residents as well as to describe several measures and alternative policies. Methods: Using the methodology of System Dynamics, we designed a simulation model of the allocation process. Based on the validated model, possible changes in the system through time in response to diverse allocation policies were simulated. Specifically, changes in the accumulated number of graduates who over the years have remained without specialty, the number of unemployed specialists, and the imbalance between supply and demand in the period under consideration were observed. Results: The results obtained from the simulation indicate that allocation policies such as the current one tends to reduce the accumulated number of graduates without specialty, due to the philosophy characterizing this policy, but that it considerably increases the number of unemployed specialists and aggravates the supply-demand imbalance. In the simulation, this tendency remained over time even though more restrictive measures in numerus clausus and retirement age were adopted. Equally, a policy based on social needs and aware of delays in training would substantially contribute to eliminating unemployment among specialists and supply-demand imbalance over time. If such a policy were combined with the above-mentioned measures the results would be even better, more rapidly eliminating graduates without specialty, unemployed specialists, and supply-demand imbalances. Conclusions: If the Health Administration continues with the current system of allocation of places, the present imbalance in supply and demand will become even worse. Therefore, new and far-sighted measures and policies are required, as well as greater coordination between undergraduate and postgraduate training.