Slow oscillatory transcranial direct current stimulation (so-tDCS) during slow wave sleep has no effects on declarative memory in healthy young subjects.

BACKGROUND: The manipulation of specific brain oscillations by applying transcranial electrical stimulation techniques in order to enhance memory processes during sleep has become an intriguing field of research. A seminal study found a positive effect of slow-oscillatory transcranial direct current stimulation (so-tDCS) on sleep-dependent consolidation of declarative memories. Since then several studies have tried to replicate this result with inconsistent findings. OBJECTIVE/HYPOTHESIS: This study aimed to reexamine effects of so-tDCS on declarative memory observed in young participants based on a previously described stimulation protocol used in elderly subjects. METHODS: 23 healthy participants (mean ±â€¯SD: 23.2 ±â€¯1.9 years; 13 women) completed a word-pair test and a sequential finger tapping test before and after sleep. Participants received anodal so-tDCS bifrontaly at a frequency of 0.75 Hz or sham stimulation during NREM sleep N2, following a double-blind, placebo controlled, counterbalanced, randomized crossover design. Data were analyzed with respect to possible effects of stimulation on memory performances, sleep staging, spindle densities and EEG power in eight frequency bands. RESULTS: Stimulation had no significant effect on sleep dependent memory consolidation or on sleep macro- and microstructure. Independent of stimulation, procedural memory performances increased and declarative memory performances decreased overnight. This decline was less pronounced when participants had more than one learning opportunity. Fast parietal but not slow frontal spindle densities diminished from baseline to stimulation-free intervals under both stimulation conditions. CONCLUSION: The present study could not reproduce the results of the seminal study in young subjects, but it is consistent with results observed in elderly subjects using the same protocol. Irrespective of stimulation, re-encoding opportunities in the word-pair test had an impact on memory strength and retrieval performance.

Colecistectomía laparoscópica ambulatoria. Dificultades para su implementación y desarrollo: punto de vista del paciente / Outpatient laparoscopic cholecystectomy. Difficulties in its implementation and development: point of view of the patient

Introducción: El objetivo del estudio es saber las preocupaciones y expectativas del paciente en la colecistectomía laparoscópica ambulatoria (CLA) antes de su desarrollo e implementación en nuestro Hospital. Conocer la dificultades que van a presentarse. Diseñar las medidas que deben introducirse para transmitirle seguridad, disminuir su temor y lograr su confianza y aceptación. Material y método: Estudio prospectivo iniciado en abril de 2012 y finalizado en marzo de 2013, observacional y descriptivo de los pacientes intervenidos consecutivamente de colecistectomía laparoscópica electiva con hospitalización. Participaron voluntariamente en una encuesta realizada antes y después de la operación que hacía referencia a su conocimiento y opinión de la CLA y de su predisposición a su aceptación. Resultados: Se examinaron 114 casos. Preoperatoriamente, el 46 % habrían aceptado la CLA. Este porcentaje se incrementó al 60 % en los pacientes que cumplieron criterios de selección preoperatorios de CLA (p < 0,05). Esta opinión favorable estuvo relacionada con el nivel de estudios (primarios, secundarios y universitarios: 41, 42 y 100 %, respectivamente [p < 0,01-]).Tras la intervención, solo el 18 % la hubieran preferido (p < 0,01). El único factor que contribuyó a elegir esta decisión fue el cirujano que practicó la operación que varió entre O y 43 % (p < 0,05). La causa principal del rechazo fue el temor a las posibles complicaciones. Conclusiones: La opinión del paciente es mayoritariamente desfavorable a la CLA. El cirujano deberá realizar un sobreesfuerzo informativo y docente para eliminar los prejuicios previos. Selección adecuada, estudios superiores y el cirujano apropiado pueden facilitar la aceptación de CLA (AU)

Introduction: The aim of our study is to understand the worries and expectations from the patients in ambulatory laparoscopic cholecystectomy (ALC) before the development of ALC in our Hospital. Knowing what difficulties can occur. Designing measures to be introduced to convey safety and reduce fear to the patient and allow achieve his confidence and acceptance. Material and method: Prospective study started in April 2012 and completed in March 2013, observational and descriptive of patients undergoing consecutively elective inpatient laparoscopic cholecystectomy. Voluntarily participated in a survey before and after the operation referring to their knowledge and opinion about the ALC and their predisposition to acceptance. Results: 114 cases were examined. Before the operation, 46 % would have accepted outpatient surgery option. This percentage increased to 60 % in patients who had preoperative selection criteria of ALC (p < 0.05). This favourable opinion was related to the study's level (primary, secondary and university: 41, 42 and 100 %, respectively, [p < 0.01]). Only 18 % would have accepter after the operation (p < 0.01). The only factor that contributed to choosing this decision was the surgeon who performed the operation, ranged from O to 43 % (p < 0.05). The main reason for rejection was the fear of possible complications. Conclusions: The opinion of the patient is mostly unfavourable to the ALC. The surgeon should strive to provide information and teaching to eliminate the previous prejudices of the patient. Proper selection, higher education and the appropriate surgeon may facilitate the acceptance of CLA (AU)

Molecular simulation design of a multisite solid for the abatement of cold start emissions.

A highly effective hydrocarbon (HC) trap for the abatement of cold start HC emissions with specific adsorption sites for the different molecules present in the exhaust gases has been designed by means of molecular simulation tools, and later synthesized.

Copper catalysts for soot oxidation: alumina versus perovskite supports.

Copper catalysts prepared using four supports (Mg- and Sr-modified Al2O3 and MgTiO3 and SrTiO3 perovskites) have been tested for soot oxidation by 02 and NOx/O2. Among the catalysts studied, Cu/SrTiO3 is the most active for soot oxidation by NOx/O2 and the support affects positively copper activity. With this catalyst, and under the experimental conditions used, the soot combustion by NOx/O2 presents a considerable rate from 500 degrees C (100 degrees C below the uncatalysed reaction). The Cu/ SrTiO3 catalyst is also the most effective for NOx chemisorption around 425 degrees C. The best activity of Cu/SrTiO3 can be attributed to the improved redox properties of copper originated by Cu-support interactions. This seems to be related to the presence of weakly bound oxygen on this sample. The copper species present in the catalyst Cu/SrTiO3 can be reduced more easily than those in other supports, and for this reason, this catalyst seems to be the most effective to convert NO into NO2, which explains its highest activity for soot oxidation.