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The complexity of Very High Bypass Ratio (VHBR) lean burn combustion systems requires careful fuel control and optimised staging to minimise non-volatile Particulate Matter (nvPM) emissions. Fuel flow variation across injectors will impact the temperature distribution through the turbine and thus influences rates of nvPM formation and consumption. Through Clean Sky 2, Rolls-Royce are developing technologies required for VHBR engines. CIDAR (Combustion species Imaging Diagnostics for Aero-engine Research) supports this initiative. Extractive sampling systems are the current standard method for measuring exhaust gas and fine particle emissions from various types of aircraft engines under actual operating conditions. Emerging non-intrusive approaches to gas and particulate measurement offer alternatives to extractive methods, with some significant advantages (no impact on engine performance and no hardware installed in engine exhaust, bypass or entrained flows)

Very high bypass ratio (VHBR) engines will realize significant environmental benefits as lower fuel consumption contributes to a reduction in CO2, NOx and non-volatile particulate matter (nvPM)/soot emission. VHBR engine performance tests will require representative CO2 measurement, and here we propose the use of a chemical species tomography (CST) measurement system to fully map the output CO2 from the engine core exhaust. In addition, we propose a technique allowing the 2D measurement of exhaust nvPM concentration that will provide an increased understanding of the complex injector-to-injector fuel flow variation, which impacts the temperature distribution through the turbine. This combined technological development in the CIDAR programme will produce an innovative step change in aircraft engine diagnostics, based on real-time, in-situ photonic technologies. This will increase the EU’s competitiveness in non-intrusive engine exhaust measurement systems for both engine performance evaluation and emissions quantification.

Eine neue Fluoreszenz-Fluktuations-spektroskopische Methode vereint die Vorzüge der Fluoreszenz-Korrelations-Spektroskopie mit denen helligkeitsbasierter Verfahren für hochpräzise Untersuchungen dynamischer biomolekularer Prozesse. Dieser Artikel stellt wesentliche Eigenschaften dieser neuen Methode vor.

Los extractos foliares (EF) son utilizados como complemento nutricional en países como Nicaragua y Tanzania. Se evaluaron hojas y EF de yuca, fríjol, batata y alfalfa, y se cuantificó los componentes nutricionales, antinutricionales y biodisponibilidad por métodos in vitro. En promedio (DE), el EF de fríjol tiene una elevada concentración de hierro (1006,23 (8,49) mg/kg); el EF de yuca tiene alta concentración de zinc (110,65 (6,72) mg/ kg) y proteína soluble (34,23 (3,81) g/kg). Así mismo, la digestibilidad in vitro de proteína en los EFs de yuca, fríjol y alfalfa fueron superiores a 71,18%; hierro dializable in vitro menor a 2,29%; la relación molar fitato:zinc inferior a 0,08 y la bioaccesibilidad all-trans-β -caroteno superior a 23,85%. Estos valores sugieren una alta asimilación de proteína, zinc y all-trans-β -caroteno, y una baja asimilabilidad de hierro. Los EFs pueden ser una alternativa nutricional en la alimentación en países que carecen de diversificación alimentaria.

The levels of metronidazole and pefloxacin in plasma and tissue penetration of both drugs were studied after prophylactic administration to 7 patients undergoing colorectal surgery. Metronidazole (1,500 mg) and pefloxacin (800 mg) were administered as an intravenous infusion 1 hour before surgery. Mean plasma levels of pefloxacin decreased from 12.92 +/- 4.10 microg/ml at the end of the infusion to 2.18 +/- 1.03 microg/ml at 36 h. These values were above the MIC90 for E. coli (0.125 microg/ml) and E. faecalis (0.5 microg/ml), microorganisms responsible for abdominal infections. Tissue pefloxacin levels were also measured with a range from 0.72 - 7.78 microg/g in subcutaneous cell tissue, from 1.94 - 17.55 microg/g in peritoneum and from 2.76 - 21.99 microg/g in colon wall. Mean plasma concentrations of metronidazole decreased from 39.89 +/- 17.08 microg/ml at the end of the infusion to 2.63 +/- 1.11 microg/ml at 36 h. During this period, concentrations were higher than 2 microg/ml, the MIC90 value for B. fragilis, the anaerobic pathogen more frequently involved in postoperative infections after rectal and colonic surgery. Tissue metronidazole levels ranged from 3.64 - 13.37 microg/g in subcutaneous cell tissue, from 3.26 - 41.66 microg/g in peritoneum and from 6.72 - 43.12 microg/g in colon wall. The AUC/MIC values (efficacy parameter for concentration-dependent killing antibiotics such as pefloxacin and metronidazole) obtained were the following: metronidazole AUC/MIC value for B. fragilis was 173; pefloxacin AUC/MIC values for E. coli and E. faecalis were 941 and 235, respectively. The values of these parameters are higher than the recommended values to ensure efficacy, which means good exposure of the antimicrobials to the microorganisms. In conclusion, the combination of pefloxacin and metronidazole as prophylactic agents to prevent infections in patients undergoing colorectal surgery produce plasma and tissue levels above the MIC values of the main pathogens responsible for this kind of infections.

Los extractos foliares (EF) son utilizados como complemento nutricional en países como Nicaragua y Tanzania. Se evaluaron hojas y EF de yuca, fríjol, batata y alfalfa, y se cuantificó los componentes nutricionales, antinutricionales y biodisponibilidad por métodos in vitro. En promedio (DE), el EF de fríjol tiene una elevada concentración de hierro (1006,23 (8,49) mg/kg); el EF de yuca tiene alta concentración de zinc (110,65 (6,72) mg/ kg) y proteína soluble (34,23 (3,81) g/kg). Así mismo, la digestibilidad in vitro de proteína en los EFs de yuca, fríjol y alfalfa fueron superiores a 71,18%; hierro dializable in vitro menor a 2,29%; la relación molar fitato:zinc inferior a 0,08 y la bioaccesibilidad all-trans-β -caroteno superior a 23,85%. Estos valores sugieren una alta asimilación de proteína, zinc y all-trans-β -caroteno, y una baja asimilabilidad de hierro. Los EFs pueden ser una alternativa nutricional en la alimentación en países que carecen de diversificación alimentaria. Foliar extracts (FEs) are an alternative to address food and nutrition insecurity. FEs and leaves of cassava, bean, sweet potato and alfalfa were evaluated for nutrient and antinutrient composition and in vitro nutrient bioavailability. Bean FE had a high average ± (SD) iron concentration (1006 ± 8.49 mg/kg), as did cassava FE for zinc (110.1 ± 6.72 mg/kg) and soluble protein (34.23 ± 3.81 g/kg) concentration. For the cassava, bean and alfalfa FEs in vitro protein digestibility was greater than 71.18%; in vitro iron dialyzability was less than 2.29%; the phytate:zinc molar ratio was less than 0.08, and the in vitro all-trans-β-carotene bioavailability was greater than 23.85%. These values suggest a high protein, zinc and all-trans- β -carotene bioavailability and a low iron bioavailability. FEs can be a nutritious alternative for those countries with low dietary diversity.

La muerte encefálica es una causa válida en la certificación del deceso de un paciente, especialmente en condiciones de donación de órganos. Existen escasas situaciones en las que el legislador ha propuesto la realización de exámenes complementarios para su certificación. Presentamos el caso de un paciente con un síndrome de Guillain Barré, que llegó a simular un estado de muerte encefálica, debido al compromiso motor completo, incluyendo musculatura ocular intrínseca. La falta de una condición suficiente y necesaria para declarar la muerte del paciente lleva a la solicitud de exámenes complementarios, en este caso un electroencefalograma, los que determinan la normalidad de la actividad eléctrica cerebral. Se recalca la necesidad de cumplir estrictamente los criterios para determinar la muerte encefálica y el no inhibirse de solicitar exámenes complementarios en condiciones de duda, aún cuando la ley no siempre lo contemple.

La muerte encefálica es una causa válida en la certificación del deceso de un paciente, especialmente en condiciones de donación de órganos. Existen escasas situaciones en las que el legislador ha propuesto la realización de exámenes complementarios para su certificación. Presentamos el caso de un paciente con un síndrome de Guillain Barré, que llegó a simular un estado de muerte encefálica, debido al compromiso motor completo, incluyendo musculatura ocular intrínseca. La falta de una condición suficiente y necesaria para declarar la muerte del paciente lleva a la solicitud de exámenes complementarios, en este caso un electroencefalograma, los que determinan la normalidad de la actividad eléctrica cerebral. Se recalca la necesidad de cumplir estrictamente los criterios para determinar la muerte encefálica y el no inhibirse de solicitar exámenes complementarios en condiciones de duda, aún cuando la ley no siempre lo contemple. Brain death is a valid cause of death certification in a patient, especially in terms of organ donation. There are few situations in which the legislator has proposed further examination for certification. We report the case of a patient with Guillain Barré syndrome, which came to simulate a state of brain death due to motor impairment in full, including intrinsic ocular muscles. The lack of a necessary and sufficient condition for declaring the patient's death led to request additional examinations, in this case an electroencephalogram, which determine the normality of brain electrical activity. It emphasizes the need to comply strictly with the criteria for determining brain death and not to request additional examinations inhibited in a position of doubt, even though the law does not always contemplated.

Sucralfate has been used in the prophylaxis of acute enteric toxicity induced by radiation therapy of pelvic organs. The aim of the study was to demonstrate the efficacy of sucralfate in the prevention of the acute enteric toxicity induced by pelvic irradiation in cancer patients, compared with placebo, in a multicentric double-blind randomised clinical trial.One hundred and twenty patients, with a localised pelvic cancer, 18 to 80 years old, with a Karnofsky index of 80% or more, and "normal" defecation habits (3-10 defecations/week), undergoing whole pelvic irradiation, were included. The duration of the study was 7 weeks, with weekly controls. The first week all patients received placebo. In the second week the patients were randomised into two groups: sucralfate (61 patients, 2 g/tid p.o. before meals) and placebo (59 patients). Radiotherapy started at the beginning of the third week and lasted until the end of the study. All patients received 45-50 Gy total dose (1.8-2 Gy/day, 5 days/week) with the "box technique". The main variables were the number of stools per week and the number of loperamide pills per week.The number of stools per week showed no differences between groups. By the contrary in the group intention to treat (120 patients) and per protocol (100 cases) the percentage of diarrhoeal stools per week showed a statistical significance in favour of sucralfate: (p0.05) and (p0.03) respectively, concerning the evolution of this variable from the baseline (first week) to the end of the pelvic radiotherapy (seventh week). Furthermore, the consumption of loperamide was significantly lower in the sucralfate group (p0.001).Sucralfate is effective in the preparation of acute enteric toxicity induced by pelvic irradiation.